This was the British seaborne evacuation of Czechoslovak and Polish troops, as well as civilian refugees, from the south coast of France at the time of that country’s defeat by Germany (23/26 June 1940).
By the middle of June the collapse of French resistance and the imminence of a French request for an armistice made essential the rapid implementation of rescue work over and above that already performed in undertakings such as 'Aerial', 'Cycle' and 'Dynamo', and with the least possible delay if the last of the Allied troops, much valuable shipping and all British civilian refugees, embassy and legation staffs were not to fall into German hands.
These last and hastily improvised operations began from the ports of the Gironde river estuary and moved finally to Bayonne and St Jean de Luz near the Spanish frontier. While these evacuations were in progress on the Bay of Biscay coast, however, large numbers of refugees and some Czechoslovak and Polish troops had assembled at various places on the south coast of France. On 23 June the Admiralty ordered that as many as possible should be embarked in whatever shipping could be collected for the purpose, and taken to Gibraltar. Two destroyers of Admiral Sir Andrew Cunningham’s Mediterranean Fleet were sent to organise and supervise the work, which was finished by the following midnight.
Some 10,000 Allied troops and civilians, mostly crammed in small cargo ships, were carried to Gibraltar between 24 and 26 June and thence, ultimately, to the UK.