Which civil war battle was over a river and killed 12,000 soilders on each side all together?

Tribute To The Confederate Soilders- CSA

This is in memory of my Great Great Great Uncle Marion Huckaby who fought with the 8th Infantry of Mississippi with the Moody True Blues of Clarke County….He was also a POW—– This is also for every single Confederate Soilder that either died during battle or was able to make it out alive and pass [...]