He also served as a signaller with the 2/10th Battalion in North Africa, Papua and Borneo during World War II, and was mentioned in dispatches for his bravery in action.

He worked as a labourer until he enlisted in the Second Australian Imperial Force's 2/10th Battalion in 1939 at the outbreak of World War II.

After the war he worked on the docks in Port Adelaide and became a leader of the Waterside Workers' Federation and president of the Trades and Labor Council in 1964.

Foster's victory in the historically blue-ribbon Liberal seat was part of an 18-seat swing to Labor that nearly ended the Coalition's record tenure in government.

Foster resigned from the Labor Party just before he crossed the floor to give the final vote required to pass the legislation.