Lord Lyon King of Arms. The son of a clergyman, the Rev. John Paul and Margaret Balfour (of the Balfours of Pilrig, and a cousin of author Robert Louis Stevenson), Balfour Paul trained as a lawyer and was admitted as an advocate in 1870. He went on to become Treasurer of the Faculty of Advocates (1883 - 1902) and, in 1890, was appointed Lord Lyon King of Arms, responsible for regulating heraldry in Scotland and the head of the Lyon Court. He lived in Heriot Row in Edinburgh.
Balfour Paul wrote on heraldry and history, with works including Heraldry in relation to Scottish History and Art (1890) and The Scots Peerage (9 vols, 1904-14). He was knighted in 1900.
His second son, A.F. Balfour Paul, became a noted architect in Edinburgh, while his grandson Glencairn Balfour Paul was a diplomat, who wrote on the Middle East.