While the remaining men of the 29th were on furlough in Massachusetts, Lt. Gen. Ulysses Grant, as general-in-chief of the Union Army, began the Overland Campaign. During the spring of 1864, he would direct the actions of the Army of the Potomac in northern Virginia, aggressively pushing Lee's Confederate army toward Richmond in a series of major battles. The men formerly of the 29th who had been transferred to the 36th Massachusetts took part in the opening battles of the campaign, the Battle of the Wilderness and the Battle of Spotsylvania Court House, incurring casualties of seven killed and 30 wounded out of a total of 90 men. This detachment fulfilled their three-year enlistment in mid-May 1864 and returned home.