Operation Cobra (25–31 July 1944) was the codename for an offensive launched by the First United States Army seven weeks after the D-Day landings, during the Normandy Campaign of World War II. American Lieutenant General Omar Bradley's intention was to take advantage of the German preoccupation with British and Canadian activity around the town of Caen, and immediately punch through the German defenses that were penning in his troops while the Germans were distracted and unbalanced. Once a corridor had been created, the First Army would then be able to advance into Brittany, rolling up the German flanks and freeing itself of the constraints imposed by operating in the Norman bocage countryside. After a slow start the offensive gathered momentum, and German resistance collapsed as scattered remnants of broken units fought to escape to the Seine. Lacking the resources to cope with the situation, the German response was ineffectual, and the entire Normandy front soon collapsed. Operation Cobra, together with concurrent offensives by the Second British and First Canadian Armies, was decisive in securing an Allied victory in the Normandy Campaign.
Having been delayed several times by poor weather, Operation Cobra commenced on 25 July with a concentrated aerial bombardment from thousands of Allied aircraft. Supporting offensives had drawn the bulk of German armored reserves toward the British and Canadian sector, and coupled with the general lack of men and materiel available to the Germans, it was impossible for them to form successive lines of defense. Units of VII Corps led the initial two-division assault while other First Army corps mounted supporting attacks designed to pin German units in place. Progress was slow on the first day, but opposition started to crumble once the defensive crust had been broken. By 27 July, most organized resistance had been overcome, and VII and VIII Corps were advancing rapidly, isolating the Cotentin peninsula.
WWII - European Theater of Operations/Northern France Campaign (1944)