James Buchan (born 11 June 1954) is a Scottish novelist and historian.
Buchan is the son of the late William Buchan, 3rd Baron Tweedsmuir, and grandson of John Buchan, 1st Baron Tweedsmuir, the Scottish novelist and diplomat. He has several brothers and sisters, including the writer Perdita Buchan. Educated at Eton and Magdalen College, Oxford, he began his career as a Financial Times correspondent, writing from the Middle East, Germany, and the United States. In 1986, he married Lady Evelyn Rose Phipps, daughter of Oswald Phipps, 4th Marquess of Normanby. She died in 2018. He has three children.
- A Parish of Rich Women (1984) Whitbread Book of the Year award, Betty Trask Award
- Davy Chadwick (1987)
- Slide (1991)
- Heart's Journey in Winter (1995) (The Golden Plough in US) Guardian Fiction Prize
- High Latitudes (1996)
- A Good Place to Die (1999) (The Persian Bride in US)
- The Gate of Air (2008)
- Frozen Desire: The Meaning of Money (1997)
- Capital of the Mind: How Edinburgh Changed the World (2003) (Crowded with Genius: Edinburgh's Moment of the Mind'' in US)
- Adam Smith and the Pursuit of Perfect Liberty (2006) (The Authentic Adam Smith:His Life and Ideas in US)
- Days of God: The Revolution in Iran and its Consequences (2012) The Washington Institute for Near East Policy Book Prize (Silver Medal)
- John Law: A Scottish Adventurer of the Eighteenth Century (2018)