Battle of Normandy

Operation Overlord began before dawn on 6 June 1944 with parachute and glider drops by the US 82nd and 101st Airborne Divisions in the Cotentin Peninsula and the British 6th Airborne Division east of the Orne River. At 06:30, Allied seaborne divisions assaulted five designated beaches along an 80-kilometre front. The US VII Corps secured Utah Beach and moved inland, while V Corps suffered severe casualties overcoming fortified cliff positions at Omaha. To the east, the British XXX and I Corps and the 3rd Canadian Division established lodgements on Gold, Juno, and Sword Beaches, though German resistance and counterattacks by the 21st Panzer Division prevented the capture of Caen on the first day.

Over the next six weeks, Allied operations settled into grinding attritional fighting across two distinct sectors. In the west, Omar Bradley's US First Army advanced through the dense Norman bocage to sever the Cotentin Peninsula, securing the deep-water port of Cherbourg on 26–29 June before pushing southward toward Saint-Lô. In the east, Miles Dempsey's British Second Army mounted a series of attritional armored thrusts—including Operations Epsom, Charnwood, and Goodwood—around Caen. While British armored formations suffered heavy tank losses against elite Waffen-SS and Wehrmacht panzer divisions, the operations concentrated German armor on the eastern flank and prevented Generalfeldmarschall Erwin Rommel and his successors from shifting mechanized reserves westward.

On 25 July, Bradley launched Operation Cobra west of Saint-Lô following carpet bombing by thousands of Allied aircraft. US VII Corps ruptured the German line, allowing motorized and armored columns to pour through the gap into Brittany and Maine. On 1 August, the US Third Army under George S. Patton became operational, sweeping south through Avranches and turning east. Adolf Hitler ordered a mechanized counteroffensive at Mortain on 7 August (Operation Lüttich) to reach the coast and sever Patton's supply lines. The attack failed against American defensive positions and Allied fighter-bombers, exposing German forces to complete double envelopment.

With the German 7th Army and elements of the 5th Panzer Army extended to the west, Montgomery ordered converging pincers to trap the salient. The Canadian First Army and Polish 1st Armoured Division pushed south through Falaise and Chambois, while US and Free French divisions closed in from the Argentan sector in the south. The Falaise pocket was sealed on 21 August, trapping approximately 50,000 German troops, although significant remnants escaped eastward. Allied armies pursued the surviving German formations across the Seine, liberating Paris on 25 August and driving toward the Somme and the Meuse by the end of August 1944.