On July 23, 1862, President Abraham Lincoln finally found a replacement for General George B. McClellan as General-in-Chief of the Union Army when he appointed General Henry W. Halleck. Lincoln had spent the previous 4 months as de facto head of the Army himself until he found another commander.
Digging Deeper
During the Civil War the US Army (Union Army) had a total of 4 men assigned as General-in-Chief, more or less akin to today's designation as Chief of Staff of the Army as the top soldier. The Union started the War with General Winfield Scott in charge, the 3rd Commanding General of the US Army, serving from 1841 to 1861, longer than any other Army boss.
