Armored Blitz To Avranches: How the Allies Broke Into Brittany The race for Avranches brought an end to the Americans fighting in swamps and hedgerows for incremental gains. Here's What You Need to Know: The U.S. VIII Corps exploited Operation Cobra and cracked a doorway into Brittany. Lieutenant General Omar Bradley had reason to be pleased by the last week of July 1944. His First Army had scratched out a substantial foothold on the Normandy coast, capturing three times more French territory than his British allies. He had cut off the Cherbourg peninsula to the west and pushed his army south. His carpet bombing of the German Army south of St. Lo, Operation Cobra, helped crack the enemy line. But his four corps, composed mostly of infantry, were still only inching forward. It had taken him almost two months to advance approximately 80 square miles. He needed to win the war faster than this.