During the Axis occupation of Greece between 1941 and 1944 parts of the Cham Albanian minority (, , Tsamides) in the Thesprotia prefecture, northwestern Greece, collaborated with the occupation forces. Fascist Italian as well as Nazi German propaganda promised that the region would be awarded to Albania (then in personal union with Italy) after the end of the war. As a result of this pro-Albanian approach, many Muslim Chams actively supported the Axis operations and committed a number of crimes against the local population both in Greece and Albania. Apart from the formation of a local administration and armed security battalions, a paramilitary organization named Këshilla and a resistance paramilitary group called Balli Kombetar Cam were operating in the region, manned by local Muslim Chams. The results were devastating: many Greek and Albanian citizens lost their lives and a great number of villages were burned and destroyed. It appears that the Mufti and many beys did not approve of the Cham helping the Wehrmacht to burn Greek villages. With the retreat of the Axis forces from Greece in 1944, most of the Cham population fled to Albania and revenge attacks against the remaining Chams were carried out by Greek guerrillas and villagers. When the war ended, special courts on collaboration sentenced 2,106 Chams to death in absentia. However, the war crimes remained unpunished since the criminals had already fled abroad. According to German historian Norbert Frei, the Muslim Cham minority is regarded as the "fourth occupation force" in Greece due to the collaborationist and criminal activities that large parts of the minority committed.
According to the Lieutenant Colonel Palmer of the British Military Mission in Albania, 2,000–3,000 collaborated in an organized manner, while a report of Pan-Epirotic EAM-Commission names 3,200 Cham collaborators from the Dino clan. Although not everyone in the community actively collaborated, historiography agrees that the Cham minority completely accepted the Axis occupation and benefited from the presence of occupation troops by providing them with guides, connections, informants and other forms of support. Mainly due to their collaboration in World War II the Chams later became a controversial if not suspect community for the leaders of the Peoples Republic of Albania (1945-1991).
Background
The region inhabited by the Chams, known among Albanians as "Chameria", consisted chiefly of the Thesprotia prefecture in Greece, as well as a few villages in southwestern Albania. Before 1945, the region had a mixed Greek and Albanian population dating to the migrations of Albanian tribes into the area in the 13th and 14th centuries. Many of the Chams, originally Orthodox Christians, were Islamicized in the 17th to 19th centuries, with Crypto-Christianity persisting as late as the early 19th century.
Given the Ottoman social structure, Muslim Cham landlords were a privileged part of the society and owned much of the most fertile land. Apart from the beys it seems that the majority of the Muslim Cham population consisted of middle sized land owners and also included families with ownership of small land parcels, few fields or animals and located in villages. A degree of antagonism existed between the two communities and conflict occurred on certain occasions.
Despite the claims of Greek and Albanian nationalists alike, surveys of the region of Thesprotia repeatedly noted the lack of "nationalisation" among the population; the Albanian speaking Christians referred to themselves not as Greeks but as "kaurs", while Albanophone Muslims did not call themselves "Albanian" but instead "Muslims" or "Turks"; even as late as the 1940s, the Muslims lacked any sort of Albanian consciousness and continued to describe themselves as "Turks"; Albanian nationalist ideas were espoused by a "minority of the educated and landowning class" but even these were divided between republican and royalist factions. Muslim religious authorities were conservative and of pro-Turkish persuasion, and accordingly they obstructed the growth of Albanian nationalism in the region.
Once Epirus passed to Greek hands in 1913 as a result of the Balkan Wars however, the Muslim beys lost their political influence, while retaining their economic weight. During the Interwar period, the Greek state did not take any serious effort to encourage their assimilation, although a number of complaints by the Chams to the League of Nations bear witness to a sense of grievance. However, there is little evidence of direct state persecution at this time. During that time though, members of the Cham community suffered from discrimination due to severe expropriations of their lands.