Operation Sea Lion

Operation Sea Lion () was the plan to invade the United Kingdom by Nazi Germany during World War II. However, Germany first had to control the sky and sea of the English Channel before a land invasion.
With the German Navy weakened during the German invasion of Norway and the Luftwaffe defeated at the Battle of Britain, the operation was put off on 17 September 1940 and so never happened.
Most historians believe that the German plans would have had little chance of success.