born , Dec. 31, 1815, Cádiz, Spain
died Nov. 6, 1872, Philadelphia, Pa., U.S.
U.S. general in the American Civil War .
He was the son of a U.S. naval agent in Spain. After graduating from West Point in 1835, he worked as a surveyor. He reentered the army in 1842 and in 1861 was commissioned brigadier general in the Pennsylvania volunteers. He fought at Bull Run, Antietam, and Chancellorsville. Three days before the Battle of Gettysburg , he replaced Joseph Hooker as commander of the Army of the Potomac. At Gettysburg he repulsed the Confederate attack but was criticized for failing to pursue Robert E. Lee 's forces. From 1864 he was subordinate to Gen. Ulysses S. Grant , whom he served loyally. After the war he commanded several military departments.