Before the Civil War, Grant was flailing. His business ventures had ended dismally, and despite distinguished service in the Mexican War he ended up resigning from the army in disgrace amid recurring accusations of drunkenness. But in war, Grant began to realize his remarkable potential, soaring through the ranks of the Union army, prevailing at the battle of Shiloh and in the Vicksburg campaign, and ultimately defeating the legendary Confederate general Robert E. Lee. Along the way, Grant endeared himself to President Lincoln and became his most trusted general and the strategic genius of the war effort. Grant’s military fame translated into a two-term presidency, but one plagued by corruption scandals involving his closest staff members.