Strong Vincent was born at Waterford, Erie County, Pennsylvania, 17 June 1837. He graduated from Harvard, Class of 1859, and practiced law in Erie, PA. In 1861, Vincent enlisted for 3 months in Col. John McLane's Regiment of Erie Volunteers, and was mustered out with the regiment in July 1861. He was mustered into the U. S. Army on 14 September 1861, as Lt. Col. of the 83d Pennnsylvania Volunteers. When the regiment commander, Col. McLane, was killed at Gaines' Mills on 27 June 1862, Vincent was promoted to colonel. Eventually, as senior colonel, he was given command of the 3d Brigade, consisting of the 16th Michigan, 44th New York, 83d Pennsylvania, and 20th Maine when George Sykes was given command of V Corps after George Meade was appointed Commander of the Army.
Vincent placed his brigade, in the above order from north to south around, and just below, the summit of Little Round Top, taking special care to ensure that the 83d PA and 44th NY were side-by-side. It was brigade tradition that these two units, sometimes called "Butterfield's Twins," fight next to one another (see map).
