Webster was born on 14 June 1925 on
Flinders Island,
Tasmania. He was the youngest of three sons born to Eileen (née Thorne) and
Leslie Webster. His father was the chairman of the Flinders Island Butter Factory and served as president of the
Flinders Island Municipal Council. In 1929, Webster and his family moved to his father's home state of
Victoria. His father ran a timber and hardware business in
Melbourne before settling the family on a farm in
Greenval in 1932. Webster was educated at state schools before completing his education at
Caulfield Grammar School. During World War II he managed the family farm in the absence of his older brothers, and also joined the
Air Training Corps. His father served in
state parliament from 1944 to 1947 as a member of the Country Party. Webster took business classes at the
YMCA before studying accounting at
Melbourne Technical College. He worked for periods as a clerk at a timber company, as chief clerk at a sawmill in
Orbost, and as a
tallyman on the Melbourne wharves. He was active in the
labour movement as a delegate to the Australian Timber Workers' Union and as a member of the
Waterside Workers' Federation. In 1948, he joined J. J. Webster Pty Ltd, the
Elsternwick timber, hardware, and plumbing retailer that had been founded by his grandfather in 1884. In 1954, he became a director of Lords Holdings Limited, a building supply wholesaler. ==Politics==