The 121st Pennsylvania was formed by the merger of two under-strength units in September of 1862 under Colonel Chapman Biddle. The colonel appointed Sergeant Erskine W. Hazard, Jr. of Company D as the regiment's first color bearer. The regiment then moved west from Washington to join the Pennsylvania Reserves, encamped near Antietam Creek. From there they marched with the Army of the Potomac to Fredericksburg, VA and took part in an assault on Stonewall Jackson's troops at Hamilton's Crossing, losing 138 men of 576 engaged, including Sergeant Hazard. Upon Hazard's death two other members of the regiment rescued the fallen banner.
On March 27, 1863 Sergeant William Hardy of Company B was appointed color bearer of the 121st. A native of Phoenixville, Hardy was a former employee of the Reading railroad, had served in a three month regiment, and had been employed as a hospital worker. He was also previously the bearer of the blue regimental color prior to his appointment to carry the state color.
The 121st participated in the Chancellorsville campaign, but was only lightly engaged. At Gettysburg on July 1st, 1863 the regiment fought the advancing rebels under A.P. Hill's corps on McPherson's Ridge. During the course of the day while being pushed back to Seminary Ridge by the southern advance, Sergeant Hardy escaped without a scratch, but the flag staff of the 121st was shot into three pieces, which Hardy cradled as he carried them off the field and through the town. He paused long enough to pick up a loose shingle and splinted the broken flagstaff that evening. The regimental loses on the first day's battle were 179 killed, wounded or missing out of 263 men engaged.
The 121st became part of the Fifth Corps in March of 1864 and fought in most of the major battles of Grant's Overland campaign. Sergeant William Gillespie Graham, carrying the blue regimental color was killed on the first day's battle of the Wilderness. Several days later when the regiment fought at Spotsylvania, Sergeant William Hardy was also tragically killed. The duties of color bearer would pass to Sergeant Alfred Clymer, described in records as "a mere lad . . . full of enthusiasm, fearing nothing and reckless beyond limit." The regiment took part in fighting at North Anna Church and Bethesda Church, and though it only lost five men in the later regiment, one casualty was the young Sgt. Clymer who was struck in the leg by a shell and clung to life until July 17, 1864, when he succumbed to his wound.
After Clymer was wounded, the flag was passed to Sergeant James B. Graham of Company B. Graham carried the flag until March 1865 when he was elected a Lieutenant in the newly created 214th Pennsylvania, and the flag passed to Sergeant Louis Clapper of Company C. Colonel Biddle kept the flag following the conclusion of the war and it is not known whether or by whom it was carried in the 1866 parade in Philadelphia. We do know from historical records that Clapper, who was still alive in 1914, carried the flag when they were deposited in the Capitol's main rotunda cases.