Union Order of Battle at Gettysburg
Army of the Potomac, Cavalry Corps, 1st Division

1st Div., 1st Brigade Cavalry Corps Colonel William Gamble Born in Ireland, Age 45	1st Div., 2nd Brigade Cavalry Corps Colonel Thomas Devin Born in New York, Age 40	1st Div., 3rd Brigade Cavalry Corps Brigadier General Wesley Merritt Born in New York, Age 29
Regiments: 8th Illinois | 470 men 12th Illinois | 233 men 3rd Indiana | 313 men 8th New York | 580 men | Roster	Regiments: 6th New York | 218 men | Roster 9th New York | 367 men | Roster 17th Pennsylvania | 464 men | Roster 3rd West Virigina | 59 men	Regiments: 6th Pennsylvania | 242 men | Roster 1st U.S. | 362 men 2nd U.S. | 407 men 5th U.S. | 306 men 6th U.S. | 471 men