The Polish Armed Forces in the West had fought alongside the Western Allies (primarily the United Kingdom) since 1939.
However, in the aftermath of the "Western betrayal" - the decisions reached at the Yalta conference and subsequent agreements between the Big Three - the Polish government in exile found itself no longer recognised by the allies; instead the Soviet puppet government, the Polish Committee of National Liberation, assumed control of Poland.
About 160,000 people were eligible to join, the majority of them (110,000) veterans of the Middle East campaigns, many of whom were members of the Polish II Corps.
The corps had its headquarters in Witley Camp and was commanded by Brigadier William Bain Thomas and the Polish major-general Stanisław Kopański.
They were given tuition in English and either given training in trades or employed in useful projects, often on loan to private contractors, which it was hoped would increase their chances of getting a job in civilian life.