Patton's Advance. The breakthrough occurred on July 25 near St. Lô. The recently organized American Third Army, led by General Patton, attacked through a gap in the German defenses and began one of the most brilliant campaigns of the war, a blitzkrieg turned against its developers. The Americans feinted toward the Brittany peninsula, tying up four German divisions there. At the same time, combined British and American forces stopped a German attempt to cut off the Allied thrust at Avranches. Patton's army then swung eastward in a wide arc toward Argentan, while the British drove from Caen toward Falaise. These advances encircled 100,000 German troops. Efforts to close the pocket completely were not successful, and many of the Germans escaped and set up a defensive line at the Seine river. However, some 50,000 Germans were captured.
The Americans turned eastward, deliberately forgoing the opportunity of liberating Paris. The Allied leaders had decided that a fight for Paris would slow down the advance by involving the tanks in a debilitating street battle. Sweeping south of Paris, Patton's armor moved with such speed toward the Seine that his divisions had to be supplied by air, and even then were in constant danger of running out of gasoline. Tactical air units covered his southern flank. Mantes was taken on August 19, ending German hope of halting the Allied drive at the Seine.
