In 1922, he purchased The Times newspaper following the death of its owner, Alfred Harmsworth, 1st Viscount Northcliffe. During his tenure as head of The Times, Lord Astor had the newspaper sponsor Edmund Hillary's expedition that made the first successful climb to the summit of Mount Everest. Astor remained chairman of the paper until 1959 when his son Gavin took over. In 1966, The Times was sold to Canadian newspaper tycoon, Roy Thomson.