Benjamin Griffin was born in Bradford County, Pennsylvania. He enlisted as a private in Company A, 82nd Pennsylvania Infantry on November 6, 1861. He did not see any major engagements before he was discharged for disability on August 20, 1862. The disability was not stated, but he apparently recovered quickly once he returned home.
Following the battle of Antietam, Benjamin enlisted in Company C, 6th U.S. Cavalry at Knoxville, Maryland on October 28, 1862. His enlistment documents describe him as 5’ 11 ½” tall, with dark hair, gray eyes and a light complexion. He served with his new regiment during the winter picketing of the Rappahannock, Stoneman’s Raid and the battle of Brandy Station without suffering any wounds.

During the battle of Fairfield on July 3, 1863, Private Griffin was part of Lieutenant Tattnall Paulding’s squadron fighting dismounted on the regiment’s right flank. When the Union position was overrun, he was captured trying to reach his horse. He was a prisoner of war at Belle Isle until he was exchanged January 7, 1864.

After a brief stay in Annapolis, Maryland, he returned to the regiment for duty at Cavalry Corps headquarters during the winter of 1863. He fought in the battles of the spring 1864 Overland campaign and the initial skirmishes of Sheridan’s Shenandoah Valley campaign before his enlistment expired on September 17, 1864. He was discharged at Berryville, Virginia and presumably returned home for the remainder of the war.