roads. They found Hampton's entire force in an L-shaped line behind some log breastworks two miles northwest of Trevilian. The Union cavalrymen launched seven assaults against the apex and shorter leg of the "L", but were repulsed with heavy losses. Two brigades of Fitzhugh Lee's division swung around to hit the Union right flank with a strong counterattack. The battle ended about 10 p.m. and the Union withdrew late in the night. It had been the bloodiest and largest all-cavalry engagement of the war. Sheridan, burdened with many wounded men, about 500 prisoners, and a shortage of ammunition, decided to withdraw. He planned a leisurely march back to Cold Harbor, knowing that Hampton would be obliged to follow and would be kept occupied for days, unavailable in that time to Robert E. Lee. Saint Mary's Church (June 24) Following the Battle of Trevilian Station, Sheridan's cavalry began to return on June 13 from their unsuccessful raid. They crossed the North Anna at Carpenter's Ford and then headed on the Catharpin Road in the direction of Spotsylvania Court House. On June 16 the column passed through Bowling Green and, traveling along the north bank of the Mattaponi River, arrived at King and Queen Court House on June 18. Hampton's Confederate cavalry left Trevilian Station and followed Sheridan on roughly parallel roads to the south. While Sheridan's men were off on their raid, Grant's army had begun moving from Cold Harbor to cross the James River. In conjunction with this move, Grant ordered that his principal supply base be moved from White House on the Pamunkey River to City Point on the James. Sheridan learned that the White House depot had not yet been broken up, so he sent his wounded, prisoners, and African-Americans who had been following his column, to White House under escort on June 19, and then marched back to Dunkirk, where he could cross the Mattaponi. On June 20, Fitz Lee attempted to attack the Union supply depot at White House, but Sheridan's arrival relieved the garrison there. On June 21, Sheridan crossed over the Pamunkey River, leading 900 wagons toward the James River. On June 24, Torbert's division escorted the wagons as Gregg's division followed a parallel route, protecting the right flank. At about 8 a.m., Gregg's division pushed back Confederate pickets to the north and entrenched to the west of Samaria Church (identified in Federal reports