The V2, with the technical name Aggregat 4 (A4), was the world's first long-range guided ballistic missile. The missile, powered by a liquid-propellant rocket engine, was developed during the Second World War in Nazi Germany as a "vengeance weapon" and assigned to attack Allied cities as retaliation for the Allied bombings of German cities. The V2 rocket also became the first artificial object to travel into space by crossing the Kármán line with the vertical launch of MW 18014 on 20 June 1944.

V-weapons, known in original German as Vergeltungswaffen, were a particular set of long-range artillery weapons designed for strategic bombing during World War II, particularly strategic bombing and/or aerial bombing of cities. They were the V-1, a pulsejet-powered cruise missile; the V-2, a liquid-fueled ballistic missile ; and the V-3 cannon. Germany intended to use all of these weapons in a military campaign against Britain, though only the V-1 and V-2 were so used in a campaign conducted 1944–45. After the invasion of western Europe by the Allies, these weapons were also employed against targets on the mainland of Europe, mainly in France and Belgium. Strategic bombing with V-weapons killed approximately 18,000 people, mostly civilians. The cities of London, Antwerp and Liège were the main targets.