James Gascoyne-Cecil, 4th Marquess of Salisbury son, David. James Gascoyne-Cecil, 4th Marquess of Salisbury James Edward Hubert Gascoyne-Cecil, 4th Marquess of Salisbury, (23 October 1861 – 4 April 1947), known as Viscount Cranborne from 1868 to 1903, was a British statesman. Born in London, Salisbury was the eldest son of Robert Gascoyne-Cecil, 3rd Marquess of Salisbury, who served as British Prime Minister, by his wife Georgina (née Alderson). The Right Reverend Lord William Cecil, Lord Cecil of Chelwood and Lord Quickswood were his younger brothers and Prime Minister Arthur Balfour his first cousin. He was educated at Eton and University College, Oxford, graduating BA in 1885.
Records of Prime Ministers of the United Kingdom to at least one other Prime Minister by blood or marriage. Two sets of father and son have successively held the office: The only brothers to hold the office were Henry Pelham, who was succeeded on his death in 1754 by the Duke of Newcastle. Pitt the Younger and Lord Grenville (who directly succeeded the latter in office) were the only set of full cousins to hold the office, their fathers being brothers-in-law. There have been three blood uncle-nephew sets of Prime Ministers: Lord Wilmington was two-greats uncle of Spencer Perceval, whose mother, Catherine ( Compton), Baroness Arden, was a