On April 6th & 7th, 1862, more than 100,000 men of the North and South came together at Pittsburgh Landing, Tennessee, in what came to be known as the Battle of Shiloh, named for a rustic log church located near where the fighting began. Combined casualties were nearly 24,000, killed, wounded, or missing, making it one of the Civil War's bloodiest battles.
For more information, see: http://www.nps.gov/shil/