Though Britain declared war against Germany on September 3, 1939, the Channel Islands remained largely unaffected, since the Bailiwicks of Guernsey and Jersey were self-governing British Crown dependencies. Under this political structure, their citizens were not conscripted to participate in the war effort, though some volunteered to join. As the war on the continent escalated and more Western countries were conquered, it became evident that Hitler’s army would soon overtake France and move against Britain. On June 15, 1940, the British government concluded that the Channel Islands were of no strategic importance. Despite Winston Churchill’s reluctance, Guernsey and Jersey were abandoned to the advancing German army.

Evacuation efforts were undertaken by the lieutenant governors of each island to extract British soldiers in mid-June, thereby completely demilitarizing the area and leaving the islands as so-called “open towns” for the German army. Civilian evacuation proved more difficult. Guernsey managed to evacuate roughly 80% of school-aged children, but as Guernsey was more remote than other islands and boats were scarce, they implemented a prioritized evacuation strategy. In the end, only 5,000 children and 12,000 adults out of a total population of 42,000 were evacuated. The German army, meanwhile, was not aware of the islands’ demilitarization and had prepared Operation Grünpfeil (or Green Arrow), which would have seen two battalions invade the islands had a reconnaissance pilot not reported their complete lack of defense.