World War II by country World War II by country Nearly every country and territory in the world participated in World War II, with the exception of only a few nations which remained neutral. The Second World War pitted two alliances against each other, the Axis powers and the Allied powers. The leading Axis powers were Nazi Germany, the Kingdom of Italy and the Empire of Japan; while the United Kingdom, the United States, the Soviet Union and China were the "Big Four" Allied powers. The countries involved in or affected by World War II are listed here alphabetically, with a description of their role
Operation Sledgehammer Operation Sledgehammer Operation Sledgehammer was a World War II Allied plan for a cross-Channel invasion of Europe, as the first step in helping to reduce pressure on the Soviet Red Army by establishing a Second Front, developed as a contingency alternative to Operation Roundup, the original Allied plan for the invasion of Europe in 1943. Allied forces were to seize the French Atlantic ports of either Brest or Cherbourg and areas of the Cotentin Peninsula during the early autumn of 1942, and amass troops for a breakout in the spring of 1943. The operation was eagerly pressed for by both