I'm currently writing a short essay on GoT S06E09, "The Battle of the Bastards", and one part of it focuses on the mounds of dead bodies that form. Now, I have medieval sources on Dupplin Moor and Agincourt, as well as Keegan and Roger's opinions on Agincourt, but apparently the mounds were based on accounts from the American Civil War, not from medieval accounts.
To date, the only example of something like this happening is a the "Bloody Angle", where there were so many casualties from the assaults that they filled up the trenches in front so that you could simply walk across them.
Are there any experts here who know of other examples of this happening?
I have no expertise on the American Civil War, but for Agincourt, you might also want to look at Curry's Agincourt: A New History, in place or as a supplement to Keegan, who makes some rather iffy statements and assumptions in his analysis.
It's funny, I watched the after-the-episode feature following ep. 9, and saw Benioff mention that, and it stuck out as a little odd. In short, I think I understand why he said that, as there were a few instances where casualties in one particular spot WERE extremely high, and bodies did stack up to a certain extent. However, there is maybe only one or two instances where a literal pile might have formed more than waist-high, and not to the extent that you saw in "Battle of the Bastards." Before going into any more detail, though, I would say that this is totally fine by me as far as a history mention. I think the spirit of Game of Thrones (GoT) is to give people a taste of history, albeit through a multi-generational hodge-podge and mixing of eras/conflicts, and to exaggerate for story-telling purposes (this is a fictional fantasy, after all). Nothing wrong with that.
So, there were a few instances were American Civil War (ACW) battles saw a preposterous amount of dead and wounded in one spot, and piles of bodies did occur (though again, nothing like what we saw in GoT ep. 9 where it was like 10+ feet high). On the first day during the Battle of Shiloh, for instance, Grant's forces were attacked suddenly by a hard-charging Confederate force led by Albert Sydney Johnston. The Union lines bent back at a point popularly referred to as "The Hornets Nest," and held out through about a dozen separate Confederate charges. By all accounts, it was a goddamned horror show in there for a few hours. Although the entire battlefield afterwards was said to be so covered with dead that you could walk across the field in some places without touching the ground, this particular spot was just knotted and tangled with the dead and dying. It might have been even worse had the Confederates not trained a gaggle of cannons on it after a few hours, and blew the area apart. Again, although I've never read anything about the Hornets Nest to suggest that it had bodies piled up eye-high (or higher), it would have been a ghastly sight all the same.
Others have mentioned "The Bloody Angle" during the Battle of Spotsylvania Courthouse, which likewise had a nasty concentration of action (this time it was the Confederates on the defensive). Also again, there are reports that the dead and dying were stacked up in places, but also again, nothing to the extent that we saw in "Battle of the Bastards." (This shouldn't be seen as a minimization of how really, really, really nasty the fighting was at Spotsylvania - it was straight up carnage, and it went on for hours on May 12th).
Still, if you want to point to one Civil War battle that may have come close to the level of carnage (in terms of bodies stacked up) that you saw on GoT last week, look no further than the Battle of the Crater outside of Petersberg, Virginia (July, 1864). The Union had been involved in a siege of Petersberg for about a month and a half by the end of July 1864. An idea was hatched to sap under the Confederate lines and blow a hole in their defenses, after which time the Union forces would come pouring through the breach. Long story short, racial considerations got in the way at the last minute, and an African-American division that had been training for this assault was put on the sidelines at the last minute while a clueless one took its place. The mining operations were successful in blowing a hole under the Confederate defenses, but when the Union flooded into the Crater to expose the gap, they got trapped in the "bowl" (if you will), and could not really get up and into the Rebel lines in force. What followed was an unmitigated disaster where more and more Union troops kept pouring into this crater, with few being able to get out (the new division assigned forgot the ladders). The Union forces got pressed in on each other, and the Confederates just started slaughtering them en masse. In this instance, there were indeed piles upon piles of bodies, and the compression and squeezing you saw on GoT combined with the staggering number of bodies in so small a space did create an effect somewhat similar to what we saw on TV. For reference, if you've seen the beginning of the movie "Cold Mountain," this is the battle portrayed.
Hope this helps!!
[Sources: Bruce Catton, 'A Stillness at Appomattox" & "Grant Takes Command"; James McPherson, 'Battle Cry of Freedom'; Shelby Foote, 'The Civil War, vol. 3']
I am not sure I understand...for the Civil War? Bloody Lane at Antietam. That had over 5,000 casualties on something like 700 yards of sunken road, a road about eight feet wide.