Buford was born in Kentucky, but had moved to Illinois before being appointed to West Point. He graduated in 1848 and was posted to the dragoons, a word used for mounted infantry, where he saw some action along the frontier and in the expedition against the Mormons in Utah in 1857-1858. Henry Sibley and Edward Canby, who would later face off against each other in the Civil War Battle of Valverde, were also involved in the Mormon Campaign.
Buford began the Civil War serving in the staff of the defenses around Washington D.C. He then received a position on Pope's staff in northern Virginia, where he was rewarded a brigadier's star and command of a brigade of cavalry. Two of his brigades initiated the fighting northwest of Gettysburg. Buford managed to hold off the Confederate assaults until Union infantry enabled General Meade to make a stand south and east of the town on the next two days.
Buford contracted typhoid and had to relinquish his command on November 21, 1863. He was promoted to major general of volunteers just before he died in Washington on December 16, 1863.