Marquess of Salisbury  Marquess of Salisbury is a title in the Peerage of Great Britain. It was created in 1789 for the 7th Earl of Salisbury. Most of the holders of the title have been prominent in British political life over the last two centuries, particularly the 3rd Marquess, who served three times as Prime Minister in the late 19th and early 20th centuries. This branch of the Cecil family descends from Sir Robert Cecil, the son of the prominent statesman the 1st Baron Burghley, from his second marriage, to Mildred Cooke. His elder half-brother the 2nd Baron Burghley, was created Earl of Exeter in 1605 and is the ancestor of the Marquesses of Exeter. Cecil notably served under Queen Elizabeth I and later King James I as Secretary of State, Chancellor of the Duchy of Lancaster, Lord Privy Seal and Lord High Treasurer. In 1603 he was raised to the Peerage of England as Baron Cecil, of Essendon in the County of Rutland, and the following year he was created Viscount Cranborne. In 1605 he was further created Earl of Salisbury. The last two titles were also in the Peerage of England. The Earl of Salisbury was succeeded by his son, the second Earl. He represented Weymouth in the House of Commons and also served as Captain of the Honourable Band of Gentlemen Pensioners and as Lord Lieutenant of Hertfordshire and Dorsetshire. His great-grandson, the fourth Earl, converted to Roman Catholicism and in 1689 the House of Commons decided to impeach him for high treason. However, the charges were not brought any further and he was succeeded by his son, the fifth Earl, Lord Lieutenant of Hertfordshire. The seventh Earl was a politician and served as Lord Chamberlain of the Household for many years. In 1789, he was created Marquess of Salisbury in the Peerage of Great Britain. He was succeeded by his eldest son, the second Marquess. He was a Conservative politician and held office as Lord Privy Seal and Lord President of the Council. Lord Salisbury married as his first wife Frances Mary Gascoyne, daughter of Bamber Gascoyne, in 1821. The same year he assumed by Royal licence the additional surname of Gascoyne. He was succeeded by his third but eldest surviving son, the third Marquess. The third Marquess was three times Prime Minister of the United Kingdom, from 1885 to 1886, 1886 to 1892 and 1895 to 1902 and also served four times as Foreign Secretary.