Codenamed Operation Neptune, the largest seaborne invasion in history and the start of Operation Overlord took place on Tuesday, 6 June 1944 when a huge Allied force began the liberation of German-occupied France. The culmination of a years planning, and even then, it was almost scuppered by the weather, D-Day encompassed an assault on five beaches – Gold, Juno and Sword by British & Commonwealth forces, with Utah & Gold by the US.
Starting with an extensive aerial and naval bombardment and an airborne assault, Allied troops swarmed ashore and encountered heavy resistance, on the beach where the US forces landed, and further inland elsewhere. Casualties were heaviest at Omaha, with its high cliffs and the landing craft came under heavy fire from gun enplacements.
Despite failing to acheive any first day objectives, the push was relentless and eventually led to a break out from the landing zones. The securing of the beaches and the subsequent construction of two Mulberry Harbours led to an influx of men and material that overwhelmed the defending German Army. A rapid securing of air superiority and continued naval dominance meant the days of effective resistance in the West were numbered.