The Battle of Shiloh took place in Tennessee over two days in April 1862 and was one of the early major battles of the Civil War between inexperienced Union and Confederate armies led by Generals Ulysses S. Grant and Albert S. Johnston respectively. The Confederates launched a surprise attack on the first day, but the Union troops received reinforcements and turned the tide on the second day, though both sides suffered heavy casualties, especially from the death of General Johnston who was the highest ranking general killed during the war.