When did the man who Lord Frederick Charles Cavendish was a protege of last serve as Prime Minister?
Lord Frederick Cavendish Lord Frederick Charles Cavendish {'1': ", '2': ", '3': ", '4': "} (30 November 1836 – 6 May 1882) was an English Liberal politician and "protégé" of the Prime Minister, William Ewart Gladstone. Cavendish was appointed Chief Secretary for Ireland in May 1882 but was murdered only hours after his arrival in Dublin, a victim of the politically motivated Phoenix Park murders.
Archibald Sinclair, 1st Viscount Thurso Archibald Henry Macdonald Sinclair, 1st Viscount Thurso, {'1': ", '2': ", '3': ", '4': "} (22 October 1890 – 15 June 1970), known as Sir Archibald Sinclair, Bt, between 1912 and 1952, and often as Archie Sinclair, was a British politician and leader of the Liberal Party.