Writer, broadcaster and founding question-master of BBC television's 'Mastermind' quiz programme. Magnusson was born in Reykjavik (Iceland), but brought as a baby to Edinburgh, where his father was Icelandic Consul. He was educated at Edinburgh Academy and Jesus College, Oxford. Magnusson became a journalist with the Scottish Daily Express and then Scotsman newspapers, before joining the BBC, initially on the Tonight programme. He went on to be responsible for programmes such as Chronicle and BC: The Archaeology of the Bible lands, as well as Mastermind, which ran for 25 years.
A prolific author and translator, with books which include Introducing Archaeology (1972), Treasures of Scotland (1981), The Complete Book of British Birds (1992), Scotland Since Prehistory: Natural Change and Human Impact (1993) with T. Christopher Smout, The Vikings (2000), Scotland: The Story of a Nation (2000), Lindisfarne (2004), Keeping My Words (2004), Fakers, Forgers and Phoneys: Famous Scams and Scamps (2006), together with translations of several Norse sagas and the novels of Icelandic Nobel laureate Halldor Laxness.
Magnusson also served as Chairman of the Ancient Monuments Board for Scotland (1981-89), Chairman of Scottish Natural Heritage (1992-99), the government organisation responsible for managing Scotland's environment, was Rector of the University of Edinburgh (1975-8) and Chancellor of Glasgow Caledonian University (from 2002). He held honorary degrees from the Universities of Edinburgh (1978), Strathclyde (1993), Paisley (1993) and Napier (1994). Having always maintained his Icelandic citizenship, he was awarded an honorary knighthood in 1989 for services to the heritage of Scotland.
Magnusson died at his home near Balmore (East Dunbartonshire).