Various local unions of factory workers were established in Belgium around the turn of the 20th century.
Initially a small organization with only 3,500 members in 1913, it experienced rapid growth during World War I, reaching a membership of 51,283 by 1920.
Consequently, at the beginning of 1921, it merged with the recently founded Building and Wood Workers' Union to form the General Union of Building, Furnishing and Other Industries.
[1] The union was led by national secretary August De Bruyne.
From 1919, Dore Smets also served as a district secretary.