After leaving school at the age of fourteen, Welensky found employment with Rhodesia Railways as a fireman, while putting his physical strength to work as a boxer. He rose through the ranks of Rhodesia Railways to become a locomotive engine driver and became involved in the trade union movement, joining the Rhodesian Railway Workers' Union. After participating in the unsuccessful 1929 Rhodesian Railways strike, Welensky was moved by management to Broken Hill, the main base of the railways in Northern Rhodesia. In 1933, he became Chairman of the Broken Hill branch of the union, and was appointed to the National Council.