In February 1903 Wilhelm Hauschild wrote a letter to the bosses of Bayer AG. Signed by 170 workers, it asked for support in founding a works sports club. That club became Turn- und Spielverein Bayer 04 Leverkusen. From 1949 to 1975 the club moved between leagues below the professional level. In 1974/75 it qualified for the 2. Bundesliga and in 1979 achieved promotion to the Bundesliga.