The Peninsula Pinkerton and Mac

[Saphroneth]

So, in fact, the planning of the Urbana and Peninsula Operations were Both initiated by McClellan?

McClellan was going to initiate his Urbana Plan, even in the face of Johnston's recent movements, if he had not been prevented by his Corps Commanders?

The Urbana plan is still quite workable in the face of Johnston having moved back to the Rapidan and Rappahannock, it's just not something he's completely unable to respond to in a timely fashion. So yes, McClellan probably would have initiated it "if he had not been prevented by his Corps commanders"; he'd been planning it for months, after all. (Though given that Lincoln had already agreed with the plan and then asked for a re-vote, one might as well say Lincoln was the one who prevented it - one would think Lincoln could just order the plan skotched, mind you.)

McClellan considered multiple landing sites, but rejected the Peninsula as inferior to Urbana after a study in January IIRC. It was the Corps Commanders who selected the Peninsular landing site, and McClellan then had to refactor his planning for Urbana into planning for a landing on the Peninsula.

Do you know the weak spots chosen by McClellan's Engineers?

Yes, Garrow Ridge (the only place where the left bank is higher than the right) as the shield for the forming up point (modern term) and as the place upon which to put artillery to gain fire superiority, Dam Number One and the nearby shallow section of the river (fordable) as the crossing point itself. This was the only place where artillery fire superiority could be established to get over the river and a lodgement thus gained.

There's actually not many places an attack is possible at all, the question is which one is the weakest. The other possible option is the Red and White Redoubts, but that's two strong redoubts connected by an earthwork, covered by torpedoes (land mines) and a wide open belt, and occupied by 20 guns and a large brigade even on April 5-6. Weaker positions repelled strong attack columns at Vicksburg.

 

[Nathan Towne]

Yes, that's what I'm arguing in favour of - I just think collapsing it down to end-siege strength (for either side) isn't really a true picture of the situation at the time, because there's the possibility that the position was weak to be stormed into earlier (and that needs to be evaluated on the situation at the time). It certainly wasn't later in the siege when Johnston has more men than he needs to fill the entrencments.

Well, there was much back and forth between Johnston and the government from March 24th through March 27th, when Johnston was instructed to send about 10,000 men to the Peninsula. Now, of course, Johnston would be provided with discretion beyond this (we don't need to get into the specifics of that), but such was the original order. Ultimately, it would be filled principally via units not with the main body of Johnston's Army. The government, within a few days, ordered Cadmus Wilcox's brigade to be detached from Holmes' force which had been ordered to North Carolina and ordered Raleigh Colston's brigade to the Peninsula from Norfolk. Howell Cobb's brigade had also been ordered to the Peninsula from Norfolk, along with a spattering of other regiments.

On April 3rd, in spite of the demonstrations along the Rappahannock, Lee messaged Johnston for another 10,000 men.

I would certainly agree with @OpnCoronet if all that he is saying that way is that in these days, U.S. force on the Peninsula was accumulating very rapidly relative to Confederate force. Of course, the storm, commencing on April 6th, would impose serious challenges, but it wouldn't necessarily completely negate an attack. By that point, Magruder probably had around 20,000 men.

Magruder's whole force was about 12,000 men, or so, total, prior to reinforcement beginning in early April.

 

[Belfoured]

The first March meeting (March 7 IIRC) had a vote, and had as a conclusion that Urbana should be enacted. One week later (March 12-13) Lincoln asked for a second vote by a different subset of people, and that second vote instituted the Peninsular campaign.

I do not know how I can state this any clearer. The Peninsular plan was not McClellan's first choice (that was Urbana) but he deferred to Lincoln's wishes, which was the result of the March 12-13 corps commander vote; that result was to launch the Peninsula, provided that naval support was available (which Keyes said he had confirmed that day) and that 40,000 men were left to defend Washington.


As for how McClellan began active field operations, McClellan ordered both his columns (the right flank led by Porter and the left flank under Keyes) to attack as soon as they reached the line. Both commanders declined to attack because of the strength of the line, which was obvious to them without having to get a thousand men killed.

We actually do know many of the details of the defences - such as that Lee's Mill (where McClellan ordered a bayonet assault and Keyes declined to launch such an attack) is a bridge with a large brigade covering it and 11 guns in nearby defensive works, and with Magruder's main reserve only a mile or so behind it. This is not a position that can be taken at a rush, it is a bridge defended by about as many troops as you can defend a bridge with - at least at the point of attack.



Would you be so kind as to post that part of Johnston's inspection report, including which position was identified by Johnston as the weak point of the line? So far as I'm aware Johnston disapproved most of the Red and White Redoubts (as they were built on the forward crest, making them vulnerable to long range rifled artillery fire) while the point of attack that McClellan's engineers selected was Garrow Ridge - a position which neither one of McClellan's columns was aimed at, meaning that it wasn't even found until the scout work was done.

According to Newton, the problems in Johnston's eyes weren't limited to "vulnerab[ility] to long range rifle artillery fire". Newton states regarding the trenches extending S/SE from the Yorktown position [Dissertation p. 228-229]:

"Four hundred yards of trenches, fairly well covered by abatis, extended south from the front corner of the Yorktown works. While adequate as an extension of the main work, this row of rifle pits suffered from two major defects. The row dead-ended in a swamp, rather than connecting with the entrenchments around Magruder's secondary redoubts between Yorktown and the Warwick River. As a result, infantry stationed there could neither reinforce the positions to their right nor be quickly withdrawn if threatened with overwhelming numbers. The second deficiency was the lack of a drainage system; soldiers standing guard or fighting from those trenches would have to do so in water that varied from ankle- to knee-deep."

Next Newton states [p. 230]:

"The trenches that extended from Fort Magruder to the smaller redoubt were extensive and somewhat better drained than
those immediately around Yorktown. Their layout seemed haphazard, almost as if they had been dug by troops interested
in protecting their own camps rather than laid out by engineers seeking to establish effective lines of fire. The entire system spanned about 800 yards of the front, but did not join the works at Yorktown on the left or the Warwick defenses on the right."

He adds [p. 230-231]:

"Only a broken line of rifle pits, crowned with varying heights of parapets and filled to varying depths with water, connected the redoubts to Magruder's next defensive point at Wynn's Mill. This did not appear that dangerous from a defensive point of view, because the two generals could see that the area in front of these irregular entrenchments had been flooded by closing the Warwick River dams. Nonetheless, the question remained: how quickly could a brigade be moved laterally from the redoubts across nearly 3,000 yards of broken ground to support Wynn's Mill in case of an emergency."

Finally, noting that Early attempted to inform Johnston about the weaknesses of his own line at Wynn's Mill but that Johnston had made up his mind, Newton states that Johnston met Magruder [p. 231]:

"It is questionable whether Johnston and Whiting travelled any farther down the Warwick than Wynn's Mill. It is also not certain just when Magruder joined his new commander; he had not been informed of Johnston's visit in advance. Magruder did not attempt to hide or rationalize the deficiencies of his line, for he had never claimed it to be anything more than a hasty expedient occupied as a last resort."

 

[Saphroneth]

I would certainly agree with @OpnCoronet if all that he is saying that way is that in these days, up through say the storm on April 6th, U.S. force on the Peninsula was accumulating very rapidly relative to Confederate force. Of course, the storm would impose challenges, but it wouldn't negate an attack.

Well, it's tricky. A lot of troops arrived from different places during the early siege, not just from Johnston's army. For example, my notes make it that Magruder's nadir of strength was late March, at 11,493 (in late-April effectives) and that from that date to April 3rd he gained about 5,000 more effectives. Another ~3,000 arrived on the 4th-5th, then a further ~5,300 on the 6th and ~2,500 more on the 7th.

In other words, from April 3rd to April 7th Magruder's strength increases by more than 50%.

Interestingly enough April 5 (the actual day of contact with the Yorktown line) does actually seem to be the day on which the ratio of available Union troops to available Confederate troops is the highest, at least assuming that the swap of Casey for Hamilton is required to make Hamilton available (on the 3rd) and that it takes two days to march from the camps south of the Big Bethel line to the Yorktown line.


The storm makes an attack anywhere very difficult, especially anywhere between the Red and White Redoubts (which are on the high ground between the streams flowing into the York and the ones flowing into the Warwick) and Lee's Mill where there's a bridge. Given the marshy ground I'd be leery - what attacks do take place in the middle of storms? One doubts it's common.

 

[Nathan Towne]

Well, it's tricky. A lot of troops arrived from different places during the early siege, not just from Johnston's army. For example, my notes make it that Magruder's nadir of strength was late March, at 11,493 (in late-April effectives) and that from that date to March 3rd he gained about 5,000 more effectives. Another ~3,000 arrived on the 4th-5th, then a further ~5,300 on the 6th and ~2,500 more on the 7th.

In other words, from March 3rd to March 7th Magruder's strength increases by more than 50%.

Interestingly enough April 5 (the actual day of contact with the Yorktown line) does actually seem to be the day on which the ratio of available Union troops to available Confederate troops is the highest, at least assuming that the swap of Casey for Hamilton is required to make Hamilton available (on the 3rd) and that it takes two days to march from the camps south of the Big Bethel line to the Yorktown line.


The storm makes an attack anywhere very difficult, especially anywhere between the Red and White Redoubts (which are on the high ground between the streams flowing into the York and the ones flowing into the Warwick) and Lee's Mill where there's a bridge. Given the marshy ground I'd be leery - what attacks do take place in the middle of storms? One doubts it's common.

You mean from April 3rd to April 7th.

 

[Saphroneth]

Newton states regarding the trenches extending S/SE from the Yorktown position [Dissertation p. 228-229]:

So by the looks of things the principal issue that comes up is that there's not good lateral communication - that is, the ability of troops to march left and right along the line is at question, specifically that the Red and White Redoubt section is not connected well with the sections to either side (which is mentioned no less than three times) - and aside from that it's mostly drainage issues. Those drainage issues are probably related to the significant sickness reported during the siege, but they don't render the line ineffective against direct attack - just ask anyone at Passchendale.


Lateral communication problems only really makes the line weak if a commander can feint at one position heavily enough to draw away reserves, and then attack at another (as the mis-deployed reserves cannot correct their poor deployment so readily). This might well be possible, but is it something that McClellan can do on the 5th or 6th? By the 10th Magruder has over 30,000 effectives and can cover every possible crossing point much more effectively.

I note you mention weakness at Wynn's Mill, but that's not really a crossing point per se - it's dry at low tide, but it's been flooded by the closing of the sluice gates.

You mean from April 3rd to April 7th.

Yes I do, mea culpa, I'll go back and edit that.

 

[Nathan Towne]

So by the looks of things the principal issue that comes up is that there's not good lateral communication - that is, the ability of troops to march left and right along the line is at question, specifically that the Red and White Redoubt section is not connected well with the sections to either side (which is mentioned no less than three times) - and aside from that it's mostly drainage issues. Those drainage issues are probably related to the significant sickness reported during the siege, but they don't render the line ineffective against direct attack - just ask anyone at Passchendale.


Lateral communication problems only really makes the line weak if a commander can feint at one position heavily enough to draw away reserves, and then attack at another (as the mis-deployed reserves cannot correct their poor deployment so readily). This might well be possible, but is it something that McClellan can do on the 5th or 6th? By the 10th Magruder has over 30,000 effectives and can cover every possible crossing point much more effectively.

I note you mention weakness at Wynn's Mill, but that's not really a crossing point per se - it's dry at low tide, but it's been flooded by the closing of the sluice gates.


Yes I do, mea culpa, I'll go back and edit that.

No worries.

Again, Magruder only had about 12,000 men prior to reinforcement.

We have the basic timetable for Confederate reinforcement which @67th Tigers accurately provided above up through April 5th.

As I wrote above, the first order, calling for 10,000 men from Johnston's Army was the March 27th order. Ultimately, the government would essentially order Wilcox's, Colston's and Cobb's brigades, along with a spattering of other regiments to the Peninsula.

On April 3rd, even though U.S. forces were heavily demonstrating along the Rappahannock, Johnston was sent and received the dispatch for an additional 10,000 men.

Additional forces were ordered to the Peninsula in response to the April 3rd order. From Johnston's main body, they boarded trains at Orange Court House on April 5th and travelled to Richmond. Rodes brigade led the movement. It was probably in this movement that the disaster with the Sixth Alabama occurred. From there, they began the movement to the Peninsula. I remember that Rodes brigade, again in the lead, were sent from Broad Street Depot down to the docks and loaded onto steamers from where they were shipped to a points behind the Warwick line, offloaded and then moved to the front from there. They came up early on the 7th, with the remainder of the division following.

 

[Nathan Towne]

@Saphroneth

I believe that Rodes brigade led the movement in response to the April 3rd order from the main body of Johnston's Army.

 

[Nathan Towne]

Was the numerical discrepancy any more than during Chancellorsville or Gettysburg? My point is, deep in enemy territory, the initiative must be maintained.

Whatever the 'discrepancy' it was in favor of McClellan, and he did not even try the defenses Yorktown.

@OpnCoronet

Well, again, it depends when we are talking about. McClellan set the movement in motion against the Warwick Line on April 3rd, I believe. By April 5th, when U.S. forces began to make substantial contact, Magruder's strength had swelled from about 12,000 men, to around 20,000 men. The storm appears to have hit sometime later in the day on the 6th, although I am not entirely sure when. This didn't necessarily make offensive operations impossible, but it would have certainly made things quite a bit more difficult.

Interestingly, we have the reports from Thaddeus Lowe for April 6th. They can be found at:

-OR Series 3, Volume 3:273-274

However, Stephen Sears, in citing them, states that the day "dawned clear and pleasant." The reports don't state that, so he must be getting that from another source, perhaps the Heintzelman Diary.

 

[67th Tigers]

@Saphroneth

I believe that Rodes brigade led the movement in response to the April 3rd order from the main body of Johnston's Army.

The order of the 3rd April set 5 brigades in motion to Yorktown, although there were some delays. Kershaw's, Rodes' and the bulk of Early's brigade got moving that day. They concentrate on the rail line, but there is a problem with the trains that delays them.

Rodes brigade was the first, and only got to Richmond on the 5th. They traveled down the James to King's Mill Landing on the 6th, and marched to the Warwick Line that night.

Kershaw's Brigade got to Richmond on the 6th, and were entrained to West Point whence they took ships directly to Yorktown on the 7th.

Early's Brigade follow Rodes route, and are one day behind. Griffith's brigade moved prettymuch with them, both arriving late on the 8th or early on the 9th. Featherston's brigade is a day behind.

 

[Nathan Towne]

The order of the 3rd April set 5 brigades in motion to Yorktown, although there were some delays. Kershaw's, Rodes' and the bulk of Early's brigade got moving that day. They concentrate on the rail line, but there is a problem with the trains that delays them.

Rodes brigade was the first, and only got to Richmond on the 5th. They traveled down the James to King's Mill Landing on the 6th, and marched to the Warwick Line that night.

Kershaw's Brigade got to Richmond on the 6th, and were entrained to West Point whence they took ships directly to Yorktown on the 7th.

Early's Brigade follow Rodes route, and are one day behind. Griffith's brigade moved prettymuch with them, both arriving late on the 8th or early on the 9th. Featherston's brigade is a day behind.

Yeah, that all sounds right.

 

[Saphroneth]

However, Stephen Sears, in citing them, states that the day "dawned clear and pleasant." The reports don't state that, so he must be getting that from another source, perhaps the Heintzelman Diary.

I wouldn't have a problem with the idea that attacks are possible for most of the day on the 6th. Really if the Warwick line is vulnerable to anything less than a full engineering attack (i.e. engineers have worked out the best point of attack) it's going to be something happening on the 6th (since most of the advancing Union force can actually get involved that day, unlike on the 5th), but even with perfect knowledge of the lay of the land it's not easy to get things coordinated.

IIRC Beattie or some other source mentions drizzle on the morning of the 5th.



One point that might be of interest is that the connection between the trenches to the (Confederate) right of Yorktown itself being unconnected with the works around the Redoubts does mean that there is technically a break in the line there (specifically the valley or ravine of Yorktown Creek), but the trenches command the valley (as noted at the time, and the valley/s are also noted as being "difficult"). Similarly, the breaks in the trench line shown on the siege plan essentially are creeks in their own right.


I wouldn't place much faith in an attack plan that involved using those breaks, so really the question is what an attack plan looks like that exploits the lack of easy communication.

One option starts to smack of trying to "perfectly choreograph" the movements of the opponent, such that you can trick them into putting extra troops (beyond the normal trench occupants) into the Redoubt trenches and then attack elsewhere.

The other option basically involves attacking the Redoubts themselves and having a bit of extra time before Confederate reserves turn up, since they have to march along the (perfectly good, prewar) road about a quarter of a mile behind the trenches instead of travelling in the trenches themselves. That might buy 15 minutes assuming that moving through trenches was as quick as moving along a road.

 

[OpnCoronet]

@OpnCoronet

Well, again, it depends when we are talking about. McClellan set the movement in motion against the Warwick Line on April 3rd, I believe. By April 5th, when U.S. forces began to make substantial contact, Magruder's strength had swelled from about 12,000 men, to around 20,000 men. The storm appears to have hit sometime later in the day on the 6th, although I am not entirely sure when. This didn't necessarily make offensive operations impossible, but it would have certainly made things quite a bit more difficult.

Interestingly, we have the reports from Thaddeus Lowe for April 6th. They can be found at:

-OR Series 3, Volume 3:273-274

However, Stephen Sears, in citing them, states that the day "dawned clear and pleasant." The reports don't state that, so he must be getting that from another source, perhaps the Heintzelman Diary.

View attachment 467771

View attachment 467772

Very informative, but I am not sure what all this has to do with McClellan , delaying to besiege a position that Johnston seemed not inclined to defend.

There seemed a division within the CSA command whether Yorktown could, or should be defended.

 

[Saphroneth]

Very informative, but I am not sure what all this has to do with McClellan , delaying to besiege a position that Johnston seemed not inclined to defend.

If he wasn't inclined to defend it, he had a funny way of showing it! Pretty much his whole army was deployed down there, except for the force left to form the Army of the North (which later became one of the large divisions used in late May and June).

 

[67th Tigers]

Here we go:


Are you serious? And I thought we were dealing with simple math here.

Only if we formulate things correctly.

Let's try stick figures. "Official count" shows "20". June 30 report shows 82 - that's 62 MORE than "official count". July 10 report shows 75. That's 55 MORE than "official count". End result - "official count" is too low by 55. I guess that's "less wrong" than being too low by 62.

How many returned after? How many wounded and dead are recorded? Are large numbers of the missing later resolved to be dead or wounded? In fact, it often took time to resolve the fates of all casualties, and they were carried as "missing" until this was known. We need longitudinal figures for all losses (including killed and wounded) before we can begin to entertain such bold claims as 55 unreported casualties.

The final figures often took weeks to sort out, and for the 61st NY it was initially reported as:

10 enlisted men killed
6 officers and 80 men wounded (and in Federal hospitals)
1 officer and 20 men missing (i.e. not accounted for in the killed or present in the hospitals)
= 117 total casualties

However, this overstated the number captured, which is recorded in the state files and transcribed by Phisterer.

19 enlisted men killed
6 officers and 80 men wounded (9 enlisted men later died of wounds)
1 officer and 11 men captured
= 117 total casualties

Whilst understating the number killed, and overstating the number captured, the totals are the same, because they count men not on parade. They can also count the number of men in their own hospitals. What they can't reliably check is the fate of those outside the lines, although the number is, of course known. In this case, 9 of those reported missing either died on the field, or in captivity, or even after exchange from their wounds. The total number of casualties does not change though.

An analysis of Phisterer's count for the 18th NY shows it is basically accurate, and those wounded at Gaines' Mill and then captured in the hospital afterwards (25) were in the missing category, not the wounded.

The "official" MIA count you've relied on is demonstrably wrong. Fact.

Perhaps, but not in the way you contend. The total casualty numbers are set, because they count the men not on parade. Often the final fates of some men remain unresolved, and the dead are sometimes recorded as missing, or perhaps a soldier reported as dead was wounded or faking it, gets captured etc.

The takehome point is that the totals are fairly immutable. We can move around within the categories, but that does not change the totals.

Use the whole dataset or GIGO.

 

[Belfoured]

Only if we formulate things correctly.



How many returned after? How many wounded and dead are recorded? Are large numbers of the missing later resolved to be dead or wounded? In fact, it often took time to resolve the fates of all casualties, and they were carried as "missing" until this was known. We need longitudinal figures for all losses (including killed and wounded) before we can begin to entertain such bold claims as 55 unreported casualties.

The final figures often took weeks to sort out, and for the 61st NY it was initially reported as:

10 enlisted men killed
6 officers and 80 men wounded (and in Federal hospitals)
1 officer and 20 men missing (i.e. not accounted for in the killed or present in the hospitals)
= 117 total casualties

However, this overstated the number captured, which is recorded in the state files and transcribed by Phisterer.

19 enlisted men killed
6 officers and 80 men wounded (9 enlisted men later died of wounds)
1 officer and 11 men captured
= 117 total casualties

Whilst understating the number killed, and overstating the number captured, the totals are the same, because they count men not on parade. They can also count the number of men in their own hospitals. What they can't reliably check is the fate of those outside the lines, although the number is, of course known. In this case, 9 of those reported missing either died on the field, or in captivity, or even after exchange from their wounds. The total number of casualties does not change though.

An analysis of Phisterer's count for the 18th NY shows it is basically accurate, and those wounded at Gaines' Mill and then captured in the hospital afterwards (25) were in the missing category, not the wounded.



Perhaps, but not in the way you contend. The total casualty numbers are set, because they count the men not on parade. Often the final fates of some men remain unresolved, and the dead are sometimes recorded as missing, or perhaps a soldier reported as dead was wounded or faking it, gets captured etc.

The takehome point is that the totals are fairly immutable. We can move around within the categories, but that does not change the totals.

Use the whole dataset or GIGO.

Confused?

 

[67th Tigers]

Confused?

No.

 

[Saphroneth]

If there were more actual casualties in the Seven Days than recorded, owing to additional captures, we would expect this to show up in that there would be MORE casualties by subtraction than casualties recorded in those units which suffered additional captured.

In many cases there are formations which have more or fewer casualties recorded than the number of casualties by subtraction (using Aggregate Present). Some of this may be due to the normal flow of men in and out of hospital.
For example, comparing AP the Reserve Artillery categories increase by 113 men despite 114 recorded casualties.

In total, factoring in the arrival of 5,225 men AP in Ferry and Kimball (not a comprehensive statement of the arrivals, since the 99th PA also arrived between the reports) as "recorded negative casualties" the number of casualties recorded by large units (broken down by division, with cavalry and reserve artillery formations separately) comes to 16,535 casualties and 5225 new arrivals, for 11,333 "expected" casualties.

The actual casualties by subtraction (difference between June 20 and July 10 AP) total to 10,205. Of these:

Kearny has the largest unexplained difference between recorded and subtracted casualties, with 1,844 more men in his July 10 strength than expected. However, much of this would be explained if the 101st NY are not on the June 20 returns under Kearny's division, along with the 99th PA.

Casey/Peck and Smith have between them 4,467 more men in their July 10 strength than expected, which appears to be most of the new arrivals (5,225, as mentioned).

The division with the largest positive anomaly (812 fewer men on their July 10 strength than expected) is Couch's division. This formation was only engaged at Malvern Hill, however, and there is no obvious avenue I can see for them to suffer excess prisoners (as the big prisoner captures were during the withdrawal south of the White Oak). Furthermore if large positive anomalies are explained by captures then large negative anomalies must be explained by something external to the army as well...

The HQ and misc. category decreases by a little over a thousand with almost no recorded casualties. Most of the decrease is in the quartermaster's guard, which goes from 1213 AP to 309 AP - this might be where the 101st NY is recorded on the June 20 return.

Overall the figures seem to largely be consistent. In aggregate present McClellan's army is about 1,100 men larger than it should be on July 10 (relative to June 20 plus recorded casualties and reinforcements) which suggests that there is no large unrecorded number of casualties.

Unit (division)​	June 20 strength AP​	July 10 strength AP​	Casualties recorded​	Casualties by subtraction​	Difference (negative is bigger unit than expected)​	Notes​
Richardson​	8792​	7383​	1284​	1409​	125​	​
Sedgwick​	9736​	9167​	1133​	569​	-564​	​
Hooker​	11097​	10096​	730​	1001​	271​	​
Kearny​	9337​	9208​	1973​	129​	-1844​	Added 99th PA​
Couch​	9359​	7871​	676​	1488​	812​	​
Casey/Peck​	6080​	7967​	124​	-1887​	-2011​	Added Ferry's bde​
Morell​	12626​	9756​	3132​	2870​	-262​	​
Sykes​	6441​	5605​	1244​	836​	-408​	​
Slocum​	9841​	7548​	2075​	2293​	218​	​
Smith​	10330​	11986​	800​	-1656​	-2456​	Added Kimball's bde​
McCall/Seymour​	9776​	7467​	3067​	2309​	-758​	​
All cavalry (Averell/Gregg/Cooke/FarnsworthMcReynolds; 1st NY, Stoneman)​	5427​	5540​	183​	-113​	-296​	​
Res Art (corps art, Hunt)​	3525​	3638​	114​	-113​	-227​	​
Sundry others (HQ, engineers, QMG, provost)​	4266​	3196​	23​	1070​	1047​	​
Column sum before reinf bdes​	116633​	​	16558​	​	​	​
Reinforcing bdes (Ferry, Kimball) - from June 30 whole union report, given in footnote​	5225​	(included)​	-5225​	(included)​	5225​	​
​	​	​	​	​	​	​
Total​	121858​	106428​	11333​	10205​	-1128​	​
​	​	​	​	​	​	​

 

[TallTallMan]

For those who have studied McClellan in detail, do you think Mac really believed the Pinkerton reports? Or was he just using the inflated estimates as excuse/cover to justify his actions?

If he was a true believer, then his cries for reinforcement and warnings how if the army is destroyed he will die with it but it won't be his fault are a little more sympathetic.

Conversely, love him or hate him, he was an intelligent man. And he clearly understood logistics. How did it not dawn on him that the estimates just didn't make sense?

"In the Civil War, for every James Bond there were two Maxwell Smarts." -James I. Robertson, Jr.

 

[Saphroneth]

Conversely, love him or hate him, he was an intelligent man. And he clearly understood logistics. How did it not dawn on him that the estimates just didn't make sense?

So to speak to this specific issue - how did it not dawn on him that the estimates just didn't make sense.



The problem is that they actually do.

As I noted, by the end of July there were 2419 companies of Confederate troops (infantry, cavalry or artillery, with each artillery battery counting as one) either at Richmond (2158 of them in the actual Seven Days, 261 having arrived since) or with Jackson's force that had moved to the north after the Seven Days.

The actual estimate for the strength at Richmond, plus Jackson's force, used internally was 252 regiments-equivalent (i.e. 2,520 companies), with the excess resulting from double counts.

This should by itself indicate that the numbers involved are not fundamentally implausible. They make sense, because the Confederates can get very nearly that number of regiments to Richmond in the sense that they are not being used anywhere else and can physically travel to Richmond.

The arrival of Beauregard's force (the separate, dubious 20,000) was a persistent rumour that McClellan kept getting from contrabands and could not rule out, but the means existed and they had not been localized anywhere else. (The source of this rumour was that Beauregard had arrived in Richmond.)




Do those regiments translate to the numbers that McClellan used?

Well, 252 regiments at 700 Aggregate Present per regiment gives 176,400, which is near enough the 180,000 used. McClellan's own strength at this time is about 175 regiments of all arms, and his per-regiment AP strength is in that ballpark.




Now, the next question is - why would the Confederates be concentrating this much strength, and is that plausible?

To my mind, the answer is - yes, it makes sense for the Confederates to concentrate this much strength if they can. It represents the worst case scenario for McClellan's own operations, but it makes strategic sense that the Confederates would concentrate everything they could muster to drive the Union away from Richmond (as in fact they actually historically did, mustering - as noted - over 215 regiments of all arms at Richmond for the Seven Days and another 26 regiments arriving afterwards.) This is because the loss of Richmond is bad for the Confederates strategically in several different ways, and because no other Union campaign in June 1862 offers anything like the same strategic threat.



In addition to all of the above (which indicates that there are good reasons why McClellan would think the Confederates would be both able and willing to do this, and that they in fact in large part did do this by concentrating all disposable forces at Richmond), it's also worth pointing out that the context also gives good reasons why McClellan would want to raise alarms about this possibility. As of May and June, the Union administration appears to be taking the view that McClellan has ample men to do the job - or that there are other operations that it wants to do which are of at least equal priority. It has promised McClellan reinforcements and then denied them to him, and as of June 20 there are about 90,000 men PFD in the East who are not in McClellan's army (despite McCall's division being sent to join him).

In this light it would make sense for McClellan to be pessimistic, though any incorrect assessments appear to have resulted in an overestimate of enemy strength of about one third (some from excess regiments, some from Beauregard) and this is actually not as much as in other known cases of overestimation.



The final point to make, though, is that the only real way in which an incorrect force estimate matters is if it leads to fundamentally incorrect decision making on the part of the one who made the estimates.

There are two things that happen during the Seven Days where it would be possible to argue McClellan committed an error about force allocation, but of these one is definitely not "there are too many enemies" and the other is probably not.

The first one is the amount of reinforcements sent to Porter. McClellan could (it could be argued) have pulled back into his defensive works, surrendering his gains from the 25th-27th, and sent more forces to Porter.
However, the forces actually sent to Porter appear to have been about right. The line broke thanks to bad luck towards the end of the day, and this bad luck event could have happened even if there'd been more troops to the north; more to the point, McClellan not sending enough troops to defend his supply line and maintaining a more offensively oriented position south of the river is hardly the sign of someone who thinks he's too heavily outnumbered.

The second one, which is complimentary, is whether or not McClellan should have attacked on the 27th south of the river. However, actually south of the river at the time (Magruder's defensive forces) were about 800 companies, which equates to about 80 regiments and thus to a bit more than two of McClellan's normal corps. (5th Corps is bigger, 4th Corps smaller, the other three are about 300-350 companies each.)
I feel that it's not really solid to argue that the forces McClellan left south of the river could have just rolled over Magruder's defensive force. Consequently, the idea that McClellan overestimated Confederate strength and thus missed out on an opportunity to attack Richmond on the 27th is to me poorly grounded.


As such, I think that the estimates were within the bounds of what could reasonably be estimated based both on fundamentals and on the information available, and that they did not drive McClellan into a fundamental misstep in the Seven Days. If anything McClellan's error in the Seven Days could be said to be that he was too aggressive, and that he could have avoided being forced away from Richmond by covering (ed: Tolopatamoy) Creek, but this would mean giving up his assault concentration and so he'd just be in a stalemate.