Ian Campbell, 4th Duke of Argyll (born 1723, died 1806), was a Scottish nobleman and politician. He was a member of the House of Lords and served as a Member of Parliament for Argyllshire. The Duke was known for his involvement in various political matters during the 18th century, particularly in relation to Scottish affairs. The 4th Duke was also a prominent figure in the Scottish Enlightenment, supporting education and the arts. He was a patron of notable figures such as the philosopher David Hume and the historian William Robertson. His contributions helped shape the cultural landscape of Scotland during his lifetime.