First German aircraft raid on British south coast towns
Strategic bombing during World War I (29 July 1914 – 11 November 1918) was principally carried out by the United Kingdom and France for the Entente Powers and Germany for the Central Powers. All the nations at war eventually engaged in such bombing, and, excepting Rome, the capital city of each major belligerent was targeted. A multi-national air force to strike at Germany was planned but never materialised. The aerial bombing of cities, intended to destroy the enemy's morale, was introduced by the Germans in the opening days of the war.
Early strategic bombing attempts led to the development of specialised bomber aircraft, during World War I. Initially bombs were dropped by hand and aimed by the naked eye, but by the end of the war bombsights had been developed. The introduction of air raid warnings and shelters can be dated to World War I, as can the design of anti-aircraft artillery and the development of methods for coordinated aerial defence.