The Commemoration of 13 February 1945 recalls the Bombing of Dresden in World War II, which killed up to 25,000 of its citizens. The lingering trauma of these attacks led to a culture of remembrance, with annual commemorative events. Regular political commemorative events had taken place in Dresden since 1946, earlier than in other German cities. The focus of these events changed several times over the years; however, since 1946, the bells of all Dresden churches have been rung on 13 February at 9:50 p.m.