When did civil defence start world war 2?

Civil defense measures in Britain began to take shape in the late 1930s, ahead of World War II, with formal organizations established by 1937. However, the extensive civil defense efforts became prominent with the outbreak of the war on September 1, 1939, when Germany invaded Poland. These measures included air raid precautions, the establishment of shelters, and the organization of volunteer services to protect civilians from bombing attacks.