On 13 June 1940 an Italian air raid took place on the RAF base at Wajir in Kenya and the air war continued until Italian forces had been pushed back from Kenya and Sudan, through Somaliland, Eritrea and Ethiopia in 1940 and early 1941. The remnants of the Italian forces in the region surrendered after the Battle of Gondar in November 1941, except for small groups that fought a guerrilla war in Ethiopia against the British until the Armistice of Cassibile in September 1943, which ended the war between Italy and the Allies. The East African campaign was the first Allied strategic victory in the war; few Italian forces escaped the region to be used in other campaigns and the Italian defeat greatly eased the flow of supplies through the Red Sea to Egypt. Most of the Commonwealth forces were transferred to North Africa to participate in the Western Desert campaign.