 The campaign peaked from mid-1940 through to the end of 1943.The Battle of the Atlantic pitted U-boats and other warships of the German "Kriegsmarine" (Navy) and aircraft of the "Luftwaffe" (Air Force) against the Royal Navy, Royal Canadian Navy, United States Navy, and Allied merchant shipping.Convoys, coming mainly from North America and predominantly going to the United Kingdom and the Soviet Union, were protected for the most part by the British and Canadian navies and air forces.