HMNB Portsmouth the military and naval units destined for Sword Beach on the Normandy coast as a part of Operation Overlord and the D-Day landings on 6 June 1944. Troops destined for each of the landing beaches left from Portsmouth aboard vessels such as the armed merchant cruisers HMCS "Prince Henry" and HMCS "Prince David", escorted by the Canadian destroyers HMCS "Algonquin" and "Sioux". The majority of the naval support for the operation left from Portsmouth, including the Mulberry Harbours. Boathouse 4 (built around the start of hostilities) contributed to the construction of landing craft and support vessels as well as more
French Forces of the Interior General Marie Pierre Kœnig, who attempted to unify resistance efforts against the Germans. General Eisenhower confirmed Koenig's command of the FFI on 23 June 1944. The FFI were mostly composed of resistance fighters who used their own weapons, although many FFI units included former French soldiers. They used civilian clothing and wore an armband with the letters "F.F.I." According to General Patton, the rapid advance of his army through France would have been impossible without the fighting aid of the FFI. General Patch estimated that from the time of the Mediterranean landings to the arrival of U.S. troops at Dijon,