Gettysburg might have been more of a psychological loss for the Confederacy (definitely for Lee and the ANV), but when they lost Vicksburg, they lost control of the Mississippi, which was a loss that affected more than self-esteem.
I don't know how you separate Vicksburg from Gettysburg and Gettysburg from Vicksburg. Together these defeats were staggering to any future Confederacy. The Confederacy never gained back what was lost, and fought an end game that was defeat for the next two years.
I think that you must include Rosecrans's pushing Bragg out of Middle Tennessee. Of course the death toll was very low and the area was much larger than the other actions that spring and summer.
Gettysburg might have been more of a psychological loss for the Confederacy (definitely for Lee and the ANV), but when they lost Vicksburg, they lost control of the Mississippi, which was a loss that affected more than self-esteem.
In terms of the overall situation, Gettysburg didn't change much, any more than the Confederate vcitories at Chancellorsville or Fredericksburg had. The East remained an ongoing stalemate, while Grant, Rosecrans, et. al. continued their progress in the West.
I agree with the above statements. IMO Gettysburg only took its significance after the war when it was realized the battle was the closest Lee came to military victory in the east. The surrender of Vicksburg (and subsequently Port Hudson) opened the Mississippi and freed thousands Union soldiers for other duties that included east Tennessee in the autumn (Sherman and Burnside) and the Atlanta Campaign the following year.
Gary Gallagher lectured on this question last summer. I believe he discussed several options, hwvr., but thought Farragut's capture of New Orleans was more significant than Vicksburg in shutting-down the Mississippi. Gallagher also pointed to Lincoln's disappointment in letting Lee get away at Gettysburg and Meade not finishing-off the ANV. Gallagher's conclusion was that the actual "turning point" in the war was bringing-in Grant to the eastern theater to chase down Lee and end the war. To answer the question though, "Gettysburg or Vicksburg," I'll go along with Grant and his brilliant Vicksburg Campaign.
I will go against the tide and say Gettysburg. Lee had a potential war-winning strike in this campaign. Had he not been stopped he could have taken Harrisburg, and possibly Philadelphia. He could possibly have set the coal fields on fire and disrupted the supply of coal the Union navy needed to maintain the blockade. The Union victory at Gettysburg dashed all those hopes. Gubernatorial elections were going to be held later in the year in the important states of Ohio and Pennsylvania, with peace candidates on the ballot. A successful confederate campaign could mean the peace candidates win and possibly start to withhold support from the Union war effort.
Gettysburg is important not for what happened as a result of it but rather what could have happened but didn't happen as a result of it. Vicksburg was little more than a symbol by this time. The food from the Trans-Mississippi had already been all but completely cut off, and the Union controlled almost the entire length of the Mississippi before Vicksburg fell.
The real turning point (in hindsight) of the Civil War was actually the Autumn of 1862 when the South was for the only time in the war on the offensive in both East and West and failed in both (Antietam/Perryville/Corinth). However the failure at Gettysburg took such a toll on General officers and regimental commanders that the AofNV was never really the same.
I think that you must include Rosecrans's pushing Bragg out of Middle Tennessee. Of course the death toll was very low and the area was much larger than the other actions that spring and summer.
Yes the Tullahoma Campaign was occurring right during the midst of the Vicksburg/Gettysburg campaigns. Rosecrans was disliked by both the War Department and by Grant who was dismissive of him in his memoirs.