The “Second Happy Time,” also known among German submarine commanders as the "American Shooting Season",[1] was the informal name for a phase in the Battle of the Atlantic during which Axis submarines attacked merchant shipping and Allied naval vessels along the east coast of North America. The first "Happy Time" was in 1940–41 in the North Atlantic and North Sea. Adolf Hitler and Benito Mussolini declared war on the United States on 11 December, 1941, so their navies could begin the “Second Happy Time.”[2]