Air and Chemical Defense League was a mass Polish paramilitary organization, founded in 1928 as a result of the merger of the State Air Defense League with the Gas Defense Society. In 1937 it numbered some 1.5 million members, with 14,000 local branches. It had a national character, gathering enthusiasts of aircraft, communications and ballooning. Between 1928 and 1939, its director was general Leon Berbecki