He will replace Sir Adrian Montague, who is leaving to spend more time in his role as Aviva’s chairman.
Thompson’s leadership style is expected to contrast with the relatively fraught relationship between outgoing chairman Montague and chief executive Simon Borrows.
Thompson will give up his directorships at energy firm Amec Foster Wheeler and Swedish manufacturer Sandvik AB, but intends to keep his non-executive job at miner Rio Tinto.
Thompson joined the board as a non-executive director yesterday, and is expected to take the reins as chairman at the annual general meeting in June.
Ex-investment banker Thompson was picked because of his wide and varied experience, according to director Jonathan Asquith, who led the search for the chairman.
“We were looking for someone who was strongly financially literate, with experience beyond financial services, who had experience as a chairman,” Asquith told City A.M.
Asquith expects Thompson to fulfill the oversight role well, arguing the new boss is “a seasoned boardroom practitioner, used to working with a high-quality, quite determined executive team... someone with good intelligence but low ego.”
Asquith himself was yesterday promoted to deputy chairman.