 Within 21st Army Group the Canadian 1st Army (under Harry Crerar) held the left flank of the Allied line, with the British 2nd Army (Miles C. Dempsey) in the center and the U.S. 9th Army (William Hood Simpson) to the south.Holding the middle of the Allied line from the 9th Army's right flank to a point about south of Mainz was the 12th Army Group under the command of Lieutenant General Omar Bradley.Bradley had two American armies, the U.S. 1st Army (Courtney Hodges) on the left (north) and the U.S. 3rd Army (George S. Patton) on the right (south).