Ulysses S. Grant commanded the Union Army.
Ulysses S. Grant . As Commanding General ( 1864 -- 69 ) , Grant worked closely with President Abraham Lincoln to lead the Union Army to victory over the Confederacy in the American Civil War . In 1862 , Grant took control of Kentucky and most of Tennessee , and led Union forces to victory in the Battle of Shiloh , earning a reputation as an aggressive commander .