After the bombings of Hiroshima and Nagasaki in 1945, the Showa Emperor announced unconditional surrender to allied forces. Over the next two years, Japan and U.S. General Douglas MacArthur cooperated in drafting the new constitution, which was ratified by the House of Representatives on August 24, 1946, by the House of Peers on October 6, and by the Privy Council on October 29, then promulgated by the Emperor on November 3, 1946, the Emperor Meiji's birthday, and came into effect on May 3, 1947.