Alexander Hannay was the son of a Presbyterian minister from Dundee, Scotland. He came to London at an early age and became a solicitor in 1881. His family was friendly with the American artist James McNeill Whistler and the Birnie Philipses in the late 1890s, and in addition to his own portrait by Whistler (in the NGA collection, 1943.11.7), he owned at least seven other paintings by the artist. Hannay is last listed in the Court Directory of the London Post Office Directory in 1917.