Confederate division at white oak Bridge

C.J.

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So I was reading the " Hooker Goes Forth: The Overland Campaign of 1863" Thread and in interesting POD by @Saphroneth came up where if a convederat division had been at the white oak bridge then McClellan may have had to surrender his army of the 7 days.so my question is.

A) is this even possible
B) what would happen after if McClellan army is now gone, what dose the Union and the Confederatcy do now. Can the Union army rebuild from this (there wher still some corps not used in the panicula campaign I think) and how fast could lee move his army from that to an attack at Maryland (sense i doubt the second manassas campaign is happening now).
 

Saphroneth

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If McClellan manages to break out anyway, then it's basically historical. If he doesn't manage to break out, and the Army of the Potomac surrenders as a result of being cut off from supply, then the Union is in serious trouble.


As of 30th June, when Pope was newly in charge of the Army of Virginia, it numbered about 68,000 PFD; this basically entailed stripping the defences of Washington (which were down to 3,800 PFD) though the Middle Department (defences of Baltimore, Harpers Ferry garrison and generally covering the north shore of the Potomac) was about 15,200. In addition to this historically about 14,000-15,000 men were pulled from Burnside and Hunter's departments to go to McClellan (and would later become 9th Corps) though these wouldn't arrive straight off owing to travel and organization time.
So the highest you can get the size of the field force able to oppose Lee is about 83,000 PFD once "9th Corps" finishes arriving in late July, and it has the disadvantage of being commanded by John Pope.

By the same measure, the Confederate army that fought in the historical Seven Days was about 112,000 PFD (this number may actually be a low estimate, as startling as it seems) and here with the extra couple of brigades' worth of troops to form the blocking division that can be estimated as about 120,000-125,000 disposable troops after the Seven Days but without taking casualties into account.

The historical Seven Days involved 20,000 Confederate casualties, of which 9,800 took place in the post-Gaines-Mill sequence; this basically means Lee has a bit more than 110,000 PFD available. He can quite feasibly invade Northern Virginia with a hundred thousand men PFD, a larger force than Pope has (historically Pope got reinforced by two corps of the Army of the Potomac and was opposed by more like 50,000 men PFD than 100,000 men PFD, and still lost badly).


Given the historical timeline of reinforcements arriving for the Union, new regiments won't start to come online until late August to September, which means that any battle in July or early-mid August is one in which Lee can confidently claim the numerical advantage (after which point very green regiments start to reinforce the Union, which redresses the numerical balance but perhaps not the combat power one); it's not really feasible that Pope can avoid engagement for a month like that without retreating into the Washington Defences, and if he does then Lee can manoeuvre against Baltimore or go north into Pennsylvania... or place Washington under close siege, if he happened to capture the AotP siege train with the army.



To summarize, it means the Union's boned.*

* this does not mean they can't win; it means they need to outperform to get through the next few months.
 

C.J.

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If McClellan manages to break out anyway, then it's basically historical. If he doesn't manage to break out, and the Army of the Potomac surrenders as a result of being cut off from supply, then the Union is in serious trouble.


As of 30th June, when Pope was newly in charge of the Army of Virginia, it numbered about 68,000 PFD; this basically entailed stripping the defences of Washington (which were down to 3,800 PFD) though the Middle Department (defences of Baltimore, Harpers Ferry garrison and generally covering the north shore of the Potomac) was about 15,200. In addition to this historically about 14,000-15,000 men were pulled from Burnside and Hunter's departments to go to McClellan (and would later become 9th Corps) though these wouldn't arrive straight off owing to travel and organization time.
So the highest you can get the size of the field force able to oppose Lee is about 83,000 PFD once "9th Corps" finishes arriving in late July, and it has the disadvantage of being commanded by John Pope.

By the same measure, the Confederate army that fought in the historical Seven Days was about 112,000 PFD (this number may actually be a low estimate, as startling as it seems) and here with the extra couple of brigades' worth of troops to form the blocking division that can be estimated as about 120,000-125,000 disposable troops after the Seven Days but without taking casualties into account.

The historical Seven Days involved 20,000 Confederate casualties, of which 9,800 took place in the post-Gaines-Mill sequence; this basically means Lee has a bit more than 110,000 PFD available. He can quite feasibly invade Northern Virginia with a hundred thousand men PFD, a larger force than Pope has (historically Pope got reinforced by two corps of the Army of the Potomac and was opposed by more like 50,000 men PFD than 100,000 men PFD, and still lost badly).


Given the historical timeline of reinforcements arriving for the Union, new regiments won't start to come online until late August to September, which means that any battle in July or early-mid August is one in which Lee can confidently claim the numerical advantage (after which point very green regiments start to reinforce the Union, which redresses the numerical balance but perhaps not the combat power one); it's not really feasible that Pope can avoid engagement for a month like that without retreating into the Washington Defences, and if he does then Lee can manoeuvre against Baltimore or go north into Pennsylvania... or place Washington under close siege, if he happened to capture the AotP siege train with the army.



To summarize, it means the Union's boned.*

* this does not mean they can't win; it means they need to outperform to get through the next few months.
It seems to me a close sige of Washington is the more likely of the two sinaorios (assuming pope dosnt get his own army destroyed before retreating to Washington) Lee seems to have always considered Washington to be the key to getting the Union to surrender, plus i have a hard time seeing Lee invading Pennsylvania if there is still a Union army in his rear. Sense Baltimore was basically stripped making pope's army then that would be a no brainer to take that however.
 

Saphroneth

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It seems to me a close sige of Washington is the more likely of the two sinaorios (assuming pope dosnt get his own army destroyed before retreating to Washington) Lee seems to have always considered Washington to be the key to getting the Union to surrender, plus i have a hard time seeing Lee invading Pennsylvania if there is still a Union army in his rear. Sense Baltimore was basically stripped making pope's army then that would be a no brainer to take that however.
Don't forget Lee did exactly that (invade PA with a Union army in the field behind him) historically!
ED: I should make it clear that in that scenario what I'm envisaging is basically that Lee heads north to try and provoke Pope into coming out of the Washington forts to fight him.
 
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C.J.

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Don't forget Lee did exactly that (invade PA with a Union army in the field behind him) historically!
ED: I should make it clear that in that scenario what I'm envisaging is basically that Lee heads north to try and provoke Pope into coming out of the Washington forts to fight him.
Ok that makes sense (and pretty similar to what Lee tried in '63) I think Pope comes out to fight would be more likely, then retreating to Washington, he simply seems like a very aggressive general to me, but we never did get to see what his decision making would be while out numbered.
 

Saphroneth

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Ok that makes sense (and pretty similar to what Lee tried in '63) I think Pope comes out to fight would be more likely, then retreating to Washington, he simply seems like a very aggressive general to me, but we never did get to see what his decision making would be while out numbered.
Historically he was willing to retreat under some circumstances, but he was also extremely arrogant and dismissive of generals who thought about their own line of retreat. So I think it's quite likely that he'd fight, and probably come off decidedly second best...

If the remaining Union army is defeated in the field, well, it depends how comprehensively. Even historically Pope got himself in such trouble that his salvation was being able to retreat behind McClellan's line formed of 2nd and 6th Corps coming up from the east, but if we assume his army isn't entirely crushed (just forced to retreat) then you've got a situation where:

- Historically, McClellan was the only general willing to go out and fight, though with him not there it's possible some other commander would have been willing to try.
- The Union army is badly mauled and to keep the forts garrisoned needs at least 15,000 men, ideally more, so that cuts into the size of the army that can go out.
- Lee probably can't assault Washington, but he could go at it by regular approaches (with siege guns - he'd only need to punch out one fort, so it wouldn't take long) or get lucky and pick the right road (there's at least one road IIRC which is not covered by a fort). Or he could go after the rail link between Washington and Baltimore and cut it off from the outside by land.
 

Generic Username

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My suspicion has been that Pope would retreat into Maryland once it becomes clear McClellan has been destroyed. Washington can be properly garrisoned and the the routes of invasion sufficiently screened with the rump Union force that Lee, even with his numerical advantage, would think twice given the nature of contested river crossings. Basically, a stalemate in the East but of such a nature that Lee can easily do what he did in 1863 historically and detach a strong field force to the West. There's also the very serious question of, with such a victory achieved, foreign recognition. Almost 100,000 Federal KIA or POW in one blow is hard to ignore...
 

Saphroneth

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My suspicion has been that Pope would retreat into Maryland once it becomes clear McClellan has been destroyed. Washington can be properly garrisoned and the the routes of invasion sufficiently screened with the rump Union force that Lee, even with his numerical advantage, would think twice given the nature of contested river crossings.
I'm not so sure about the ability to do that. If we assume Pope has a total disposable force of 85,000 (including Washington Garrison and "9th Corps") and that Harpers Ferry is garrisoned by forces from the Middle Department, then the crossing points which are sufficiently far from one another that one force can't feasibly cover more than one of them are:

Williamsport (including Falling Waters, several miles' march away)
Sharpsburg (Boteler's Ford etc)
Harpers Ferry (garrisoned from Middle Department)
Point of Rocks
Ball's Bluff (Conrad's Ferry, Edward's Ferry, Cheek's Ford)
Rockville area (Rowser's Ford, Coon's Ford)

Plus of course Washington itself.

Put a division in each of those places (50,000) and garrison Washington (15,000) and you're down to 20,000 remaining troops not accounted for, and I wouldn't want to be a division commander defending some of those locations.
 

Generic Username

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I'm not so sure about the ability to do that. If we assume Pope has a total disposable force of 85,000 (including Washington Garrison and "9th Corps") and that Harpers Ferry is garrisoned by forces from the Middle Department, then the crossing points which are sufficiently far from one another that one force can't feasibly cover more than one of them are:

Williamsport (including Falling Waters, several miles' march away)
Sharpsburg (Boteler's Ford etc)
Harpers Ferry (garrisoned from Middle Department)
Point of Rocks
Ball's Bluff (Conrad's Ferry, Edward's Ferry, Cheek's Ford)
Rockville area (Rowser's Ford, Coon's Ford)

Plus of course Washington itself.

Put a division in each of those places (50,000) and garrison Washington (15,000) and you're down to 20,000 remaining troops not accounted for, and I wouldn't want to be a division commander defending some of those locations.
Basically it would require each division to function as a trip wire and hope the 20,000 man Corps can arrive in time?
 

Saphroneth

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Basically it would require each division to function as a trip wire and hope the 20,000 man Corps can arrive in time?
Good luck with that, where would you put the corps? It's about a week's marching from Washington to Williamsport...


It's possible I'm wrong, because the amount of troops considered sufficient to defend Washington was 40,000 (15,000 garrison, 25,000 covering force) but my read on that is that it's sufficient to prevent Washington being taken (and Baltimore has its own garrison) because it means a Confederate siege can't be established. But Lee's army here is big enough that it seems like you need a lot more, because it can just overwhelm a covering force that small.

I think this probably needs to be handled in terms of Pope-move Lee-countermove, then Lee-move Pope-countermove. For example, if Pope sets up a defence along the Potomac, what does it look like/ does Pope withdraw into Washington? And then if Lee goes for Baltimore, what do his dispositions look like and what does Pope do in response?


(e.g. if Lee is going after Baltimore with 3x 25,000 man corps and leaves 1x 25,000 man corps south of the river, then Pope can't just cut Lee off from Virginia.)
 

Generic Username

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Good luck with that, where would you put the corps? It's about a week's marching from Washington to Williamsport...


It's possible I'm wrong, because the amount of troops considered sufficient to defend Washington was 40,000 (15,000 garrison, 25,000 covering force) but my read on that is that it's sufficient to prevent Washington being taken (and Baltimore has its own garrison) because it means a Confederate siege can't be established. But Lee's army here is big enough that it seems like you need a lot more, because it can just overwhelm a covering force that small.

I think this probably needs to be handled in terms of Pope-move Lee-countermove, then Lee-move Pope-countermove. For example, if Pope sets up a defence along the Potomac, what does it look like/ does Pope withdraw into Washington? And then if Lee goes for Baltimore, what do his dispositions look like and what does Pope do in response?


(e.g. if Lee is going after Baltimore with 3x 25,000 man corps and leaves 1x 25,000 man corps south of the river, then Pope can't just cut Lee off from Virginia.)
That's decisive then, as I was thinking it was only 2-3 days march.

With regards to Washington, it's actually pretty to easy to siege, which is something that gets lost a lot because of the focus on its fortifications. In the 1860s, it has only two means of resupply: the single railway line into it from the North and the Potomac itself. In late 1861, Confederate batteries placed along said river were able to shut down river traffic upon it. From the placement of Lee's Army you list, both routes of supply have thus been cut off and thus the city will fall shortly. I would suspect, based off its population size and the size of the garrison, a months time perhaps?
 

Saphroneth

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It's a good question, and it's hard to find the typical stockpile sizes in Washington/Alexandria etc. There were about 90,000-100,000 civilians within the fort ring (based on the 1860 census) and probably refugees will increase that somewhat, and then the numbr of troops inside could be anything from 20,000 to 80,000. So may as well assume 150,000 for calculation.

A month at two pounds a day (2/3 army rations) for that many would amount to about 9 million lbs, or about 4,000 tons of food; the amount of fodder that would be required is much greater per horse, but there'd be fewer horses.
 

C.J.

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It's a good question, and it's hard to find the typical stockpile sizes in Washington/Alexandria etc. There were about 90,000-100,000 civilians within the fort ring (based on the 1860 census) and probably refugees will increase that somewhat, and then the numbr of troops inside could be anything from 20,000 to 80,000. So may as well assume 150,000 for calculation.

A month at two pounds a day (2/3 army rations) for that many would amount to about 9 million lbs, or about 4,000 tons of food; the amount of fodder that would be required is much greater per horse, but there'd be fewer horses.
That seems like a lot but wasn't Washington the largest supply depot of any side during the whole war?
 

Saphroneth

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That seems like a lot but wasn't Washington the largest supply depot of any side during the whole war?
That's the question, how much they had on hand at any one time. Ideally a supply depot has a high throughput of supplies and enough to spare to make sure that no realistic interruption in the input can cause an interruption in the output, but I don't know what they'd qualify as a reasonable amount of food-on-hand.
 

C.J.

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That's the question, how much they had on hand at any one time. Ideally a supply depot has a high throughput of supplies and enough to spare to make sure that no realistic interruption in the input can cause an interruption in the output, but I don't know what they'd qualify as a reasonable amount of food-on-hand.
They where probably stocking up for the northern Virginia campaign, but I have even less of an idea then you do on how much would actually be there.
 

C.J.

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One thing I have been thinking of, what would happen to the prisoners? I don't think the Confederacy ever dealt whith that many prisoners at once at any point in the civil war. How would the Confederacy handle that.

Plus that lees army is going to be much better equipped then historically, all his troops that want rifles are going to have them plus his artillery to going to be much bigger as well even if a lot of it is probably heading west to help that struggling front.

Could the Union pull out some of its army in the west to reinforce the east? By the sige of cornith they have 120,000 men agenst 60,000 it seems they could afford to release 30,000+ to at lest to try to save the east.
 

Saphroneth

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One thing I have been thinking of, what would happen to the prisoners? I don't think the Confederacy ever dealt whith that many prisoners at once at any point in the civil war. How would the Confederacy handle that.

Plus that lees army is going to be much better equipped then historically, all his troops that want rifles are going to have them plus his artillery to going to be much bigger as well even if a lot of it is probably heading west to help that struggling front.

Could the Union pull out some of its army in the west to reinforce the east? By the sige of cornith they have 120,000 men agenst 60,000 it seems they could afford to release 30,000+ to at lest to try to save the east.
They'd probably handle it by paroles, which was the standard at this time. Possibly the Richmond garrison would be partly occupied simply in guarding the prisoners as they were gradually processed.

And yes, there was plenty of disposable force at Corinth and in the West generally. My understanding is that it would have been possible by reverting to the defensive in the West to pull out some combination of:

2 divisions of Grant's force (15,000) - Hurlbut and Sherman
Rosecrans' Army of the Mississippi (25,000).
And half of Buell's Army of the Ohio (30,000).

Transferring 55,000 men east would take up the rail lines for a month or so, but it'd be doable... the problem is that it'd take a while for the first troops to start to arrive. Lee has a window of opportunity here.
 

C.J.

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They'd probably handle it by paroles, which was the standard at this time. Possibly the Richmond garrison would be partly occupied simply in guarding the prisoners as they were gradually processed.

And yes, there was plenty of disposable force at Corinth and in the West generally. My understanding is that it would have been possible by reverting to the defensive in the West to pull out some combination of:

2 divisions of Grant's force (15,000) - Hurlbut and Sherman
Rosecrans' Army of the Mississippi (25,000).
And half of Buell's Army of the Ohio (30,000).

Transferring 55,000 men east would take up the rail lines for a month or so, but it'd be doable... the problem is that it'd take a while for the first troops to start to arrive. Lee has a window of opportunity here.
I wonder how the war in the west would go then when the Union gos on the defensive and moves half its army. Maybe the Hartland offensive gos better?

Also would this effect foreign intervention, where Britain or France ever close to coming in on the side of the Confederates after the Trent afare.

Also seems like Rosecrans would be the natural leader for the western reinforcements. Would Lincoln give up even if popes army is also defited in the field, if he has these reinforcements and the new regiments to look forward to. Probably after giving up Washington and retreating to Philly.
 
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