Born in Port Ellen, Isle of Islay, Scotland, the son of a policeman, he was educated at Dunoon Grammar School and studied economics at the Queen's College, Dundee. When he was 15 years of age, he was involved with protests against US nuclear submarines docking in Scotland.
During Robertson's time at Queen's College it broke away from the University of St Andrews to become the University of Dundee, of which Robertson was one of the first graduates (MA, 1968), and one of a minority of graduates that year who opted to take a Dundee, rather than a St Andrews, degree. During his time at University he played a full part in student life. Notably he wrote a column for the student newspaper Annasach, launched in 1967, and took an active role in student protests. Robertson used his newspaper column to back the new University and encouraged his fellow students to take a University of Dundee degree (students who had started before 1967 could opt to take a degree from either the University of Dundee or the University of St Andrews).
In 1968 Robertson was one of a number of Dundee students to invade the pitch during a rugby match at St. Andrews involving a team from the Orange Free State to protest against apartheid. The same year he organised a 24-hour work-in by students in the university library in opposition to proposed cuts by the government in student grants.
Robertson married Sandra Wallace on 1 June 1970. They have two sons and a daughter.
Robertson survived a serious crash in January 1977 of his car with a Navy Land Rover, which was carrying 100 lb of gelignite and a box of detonators, and hit his car head-on in the Drumochter Pass, leaving him with two wrecked knees and a broken jaw. Robertson was wearing a seat belt at the time and attributes his survival to this factor.
Robertson first entered the House of Commons as a Labour MP and minor entity in 1978, after having won the Hamilton by-election in May 1978, caused by the death of the incumbent Labour MP Alex Wilson in March of that year. He was challenged for the seat by the SNP candidate, Margo MacDonald, who came second. Robertson retained the constituency with an increased majority and obtained 51% of the overall vote. He was re-elected to Parliament at the five subsequent general elections, was Chairman of the Labour Party in Scotland, and was appointed to the Privy Council. After Labour won the 1997 General Election, Robertson was appointed Secretary of State for Defence, a position he held until he resigned from the Cabinet in order to become Secretary General of NATO in 1999. He was appointed as NATO Secretary General after German defence minister Rudolf Scharping declined to be nominated for the position, and doubts were raised about the suitability of British politician and former Royal Marine Paddy Ashdown (at that time the outgoing leader of the Liberal Democrats) due to his never having held a position in government.
In 1995, Robertson said that "Devolution will kill Nationalism stone dead" while he was Shadow Secretary of State for Scotland. This quote was designed to assuage fears that devolution would provide a greater platform for the Scottish National Party (SNP). Robertson's quote is frequently recalled, usually in a mocking fashion, since the SNP won Scottish Parliament elections in 2007 , 2011 and 2016.
Robertson's three children are former pupils of the school in Dunblane where gunman Thomas Hamilton murdered 16 children and their teacher in 1996. After the massacre, Robertson, a long-time resident of the town, acted as a spokesman for the victims' families. He was also a key figure in the subsequent campaign that led to the ban on handguns in Great Britain.
In 2003, the Sunday Herald newspaper ran an article entitled "Should the Dunblane dossier be kept secret?", a reference to documents relating to the Cullen Inquiry into the massacre which are to remain classified for 100 years. In a discussion board on the newspaper's website, anonymous contributors claimed that Robertson had signed a recommendation for a gun licence for Thomas Hamilton in his capacity as Hamilton's MP. In fact, Robertson had never been the gunman's MP, and the claims were totally unfounded. Robertson sued the Sunday Herald and the paper settled by paying him a five-figure sum plus costs. A subsequent action by Robertson, related to the terms of the newspaper's apology, was unsuccessful. The first case became an important test case as to whether publishers can be held responsible for comments posted on their websites.
Robertson opposed Scottish independence in the 2014 referendum.
In an article in The Washington Post, he wrote: "The residual United Kingdom would still be a major player in the world, but upon losing a third of its land mass, 5 million of its population and a huge amount of credibility, its global standing would inevitably diminish."
In a speech to the Brookings Institution on 8 April 2014 he said: "The loudest cheers for the break-up of Britain would be from our adversaries and from our enemies. For the second military power in the west to shatter this year would be cataclysmic in geo-political terms." Baron Robertson of Port Ellen also likened the efforts of Unionists to keep Scotland tied to the UK with those of Abraham Lincoln's fight against slavery when he stated, "they might look more relevantly at the Civil War where hundreds of thousands of Americans perished in a war to keep the new Union together. To Lincoln and his compatriots the Union was so precious, so important, and its integrity so valuable that rivers of blood would be spilt to keep it together."
Robertson has received numerous honours (including a total of 12 Honorary doctorates from various universities). Currently he holds directorships of several notable companies in the UK, including the Weir Group, and Cable and Wireless.
In addition, he is a Senior Counsellor at The Cohen Group, a consulting firm in Washington D.C. that provides advice and assistance in marketing and regulatory affairs.1968–1978, Official of the GMB Union for the Scottish whisky industry.
1978–1999, Member of the British House of Commons, member for Hamilton or Hamilton South, elected six times.
1979, Parliamentary Private Secretary to the Secretary of State for Social Services.
1979–??, Opposition Spokesman on Scottish Affairs.
19??–82, Opposition Spokesman on Defence.
1982–93, Opposition Spokesman on Foreign Affairs.
1983–93, Chief Opposition Spokesman on Europe.
1993–97, Shadow Secretary of State for Scotland.
May 1997, Appointed to the Privy Council
May 1997 – October 1999, Defence Secretary of the United Kingdom
October 1999 – January 2004, 10th Secretary General of NATO and Chairman of the North Atlantic Council.
Chairman of the Labour Party in Scotland
Vice-chairman of the Westminster Foundation for Democracy
Vice-Chairman of the British Council for nine years
Vice-Chairman of the Britain-Russia Centre
Member of the Council of the Royal Institute of International Affairs (Chatham House) seven years, now President
Member of the Pilgrims Society
Governor of the Ditchley Foundation
Trustee of the 21st Century Trust
Patron to the British-American Project
Currently serves on the Board of Cable & Wireless International
Currently serves on the Board of The Weir Group PLC
Currently serves on the Board of The TNK-BP
Currently serves on the Global Panel America Advisory Board
Currently a member of the Top Level Group of UK Parliamentarians for Multilateral Nuclear Disarmament and Non-proliferation, established in October 2009.
2003 Knight Grand Cross of the Order of St Michael and St George (GCMG)
30 November 2004 Knight of the Order of the Thistle (KT)
1991 Grand Cross of the Order of Merit of the Federal Republic of Germany
2000 Grand Cross of the Order of the Star of Romania
8 September 2003 Knight Grand Cross of the Order of Orange-Nassau
12 November 2003 Presidential Medal of Freedom
1 December 2003 - Grand Order of King Petar Krešimir IV
2004 Knight Grand Cross of the Order of the Cross of Terra Mariana
1993 joint Parliamentarian of the Year for his role in the Maastricht Treaty ratification
2003 Atlantic Solidarity Award bestowed by the Manfred Wörner Foundation
4th recipient of the Hanno R. Ellenbogen Citizenship Award
Elder Brother of Trinity House
24 August 1999 life peer as Baron Robertson of Port Ellen
Member of the Privy Council of the United Kingdom (PC)
Fellow of the Royal Society of Arts (FRSA)
Fellow of the Royal Society of Edinburgh (FRSE)
5 July 2006 Honorary Doctorate from the University of Paisley
Honorary Doctorate from the University of Dundee
Honorary Doctorate from the University of Bradford
Honorary Doctorate from Cranfield University (Royal Military College of Science)
Honorary Doctorate from the Baku State University
Honorary Regimental Colonel of the London Scottish (Volunteers)