World War II began in the year 1939. The conflict initiated on September 1, 1939, when Germany invaded Poland, prompting Britain and France to declare war on Germany shortly thereafter. This global conflict involved many nations and resulted in widespread destruction and loss of life. It was driven by the aggressive expansionism of Axis powers, including Germany, Italy, and Japan. The war would eventually see the involvement of multiple theaters, including Europe, Asia, and Africa, and did not officially conclude until 1945 with the unconditional surrender of the Axis powers.