World War II: Allied air forces begin attacking Germany's secret weapons bases in Operation Crossbow.

Crossbow was the code name in World War II for Anglo-American operations against the German long range reprisal weapons (V-weapons) programme.

The main V-weapons were the V-1 flying bomb and V-2 rocket – these were launched against Britain from 1944 to 1945 and used against continental European targets as well.Initial intelligence investigations in 1943 into the progress of German long range weapons were carried out under the code name Bodyline. On 15 November, a larger operation was set up under the name Crossbow. Post-war, Crossbow operations became known as "Operation Crossbow" particularly following the 1965 film of the same name.

Crossbow included strategic operations against research and development of the weapons, their manufacture, transportation and attacks on their launch site, and fighter intercepts against missiles in flight.: 7 

At one point, the British government, in near panic, demanded that upwards of 40% of bomber sorties be targeted against the launch sites.

The Crossbow attacks were futile, and every raid against a V-1 or V-2 launch site was one fewer raid against the Third Reich. The diversion of Allied resources from other targets represented a major success for Hitler.