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.
Keith Holyoake Sir Keith Jacka Holyoake {'1': ", '2': ", '3': ", '4': "} ( ;11 February 1904 – 8 December 1983) was the 26th Prime Minister of New Zealand, serving for a brief period in 1957 and then from 1960 to 1972, and also the 13th Governor-General of New Zealand, serving from 1977 to 1980. He is the only person to have held both positions.