(b. ca. 1659, Stockholm, d. 1743, London)
Swedish painter, active in England. He studied under Martin Hannibal (d. 1741) and later with David Klöcker Ehrenstrahl. In 1682 he travelled to London, where he became acquainted with Godfrey Kneller and Henry Tilson, and in 1685 he left for Europe with the latter, working briefly in Paris before proceeding to Venice and Rome, where they stayed for about two years. In Rome Dahl converted to Roman Catholicism and gravitated towards the circle of Christina, former Queen of Sweden, who sat for him (Grimsthorpe Castle, Lincs).
He returned to England with Tilson via Frankfurt and arrived in London in 1689; he stayed in England for the remainder of his career. He became for some years a rival to Kneller. He was one of the founders of the Saint Luke's Academy and was a member of the Rose and Crown Club. He died in London.