Seven UK Prime Ministers have died in office,
Spencer Compton, 1st Earl of Wilmington, who died on 2 July 1743.
Henry Pelham, who died on 6 March 1754.
Charles Watson-Wentworth, 2nd Marquess of Rockingham, who died on 1 July 1782.
William Pitt the Younger, who died on 23 January 1806 (pictured).
Spencer Perceval, who was assassinated by John Bellingham on 11 May 1812. The only one to be assassinated.
George Canning, who died on 8 August 1827.
Henry Temple, 3rd Viscount Palmerston, who died on 18 October 1865.