The union was founded in 1935 and affiliated to the South African Trades and Labour Council.
[1] It was unusual in that it admitted both black and white workers, and in Cape Town and Harrismith, they formed part of the same branches.
This position was championed by the union's general secretary, Roy du Preez.
In 1942, it helped reorganise the African Laundry Workers' Union.
In 1954, its white members split away to form a racial union.