| Honorific-Prefix: | The Most Honourable |
| The Marquess of Salisbury | |
| Honorific-Suffix: | DL |
| Office12: | Member of Parliament for Bournemouth West |
| Term Start12: | 23 February 1950 |
| Term End12: | 8 January 1954 |
| Predecessor12: | constituency established |
| Successor12: | John Eden |
| Office11: | Member of the House of Lords Lord Temporal |
| Term Start11: | 23 February 1972 |
| Term End11: | 11 November 1999 Hereditary Peerage |
| Predecessor11: | The 5th Marquess of Salisbury |
| Successor11: | seat abolished |
| Birth Name: | Robert Edward Peter Gascoyne-Cecil |
| Birth Date: | 24 October 1916 |
| Party: | Conservative |
| Parents: | Robert Gascoyne-Cecil, 5th Marquess of Salibury Elizabeth Cavendish |
| Spouse: | Marjorie Olein Wyndham-Quin |
| Children: | Robert Michael James, 7th Marquess Richard Valentine Charles Edward Vere Valentine William Henry Rose Alice Michael Hugh |
| Allegiance: |  United Kingdom |
| Unit: | Grenadier Guards |
| Battles: | World War II |
Robert Edward Peter Gascoyne-Cecil, 6th Marquess of Salisbury, (24 October 1916 - 11 July 2003), styled Viscount Cranborne from 1947 to 1972, was a British landowner and Conservative politician.
Salisbury was the eldest and only surviving son of Robert Gascoyne-Cecil, 5th Marquess of Salisbury, by Elizabeth Vere Cavendish, daughter of Lord Richard Cavendish. During the Second World War he served in the Grenadier Guards. He took part in the invasion of Normandy in 1944 with the 2nd Battalion and was a member of the first British unit to enter Brussels. He was later appointed Military Assistant to Harold Macmillan, then the Resident Minister in North Africa.
He later sat as Conservative Member of Parliament for Bournemouth West from 1950 to 1954. In 1972 he succeeded his father in the marquessate and entered the House of Lords. He also succeeded his father as President of the Conservative Monday Club. He supported The Salisbury Review and was also president of the Anglo-Rhodesian Society and Friends of the Union.
Lord Salisbury ran holdings of 8,500 acres around Hatfield House, and 1,300 acres at Cranborne Manor, Dorset. At the time of his obituary he owned property around Leicester and Leicester Square, London, held by Gascoyne Holdings.[1]
Lord Salisbury married Marjorie "Mollie" Olein Wyndham-Quin (15 July 1922 - 12 December 2016),[2] granddaughter of Windham Wyndham-Quin, 5th Earl of Dunraven and Mount-Earl, on 18 December 1945. Lady Salisbury was a noted gardener.
They had seven children: