Born in Aberdeenshire in 1883, McBey began his career as a self-taught artist. Originally a banker by trade, by 1910 he had built up the artist confidence to pursue his art on a full-time basis - travelling throughout Europe, North Africa and America. In 1912 he travelled to Morocco with the artist James Kerr Lawson, and incorporated watercolours into his oeuvre. During the First World War McBey was commissioned as a war artist, travelling widely throughout the Middle East.
In his later years, McBey lived primarily near Tangier in Morocco, although spent the final three years of the Second World War in America. After the war he returned to live in Tangier, but returned regularly to Britain and the United States. He died in Tangier, Morocco in 1959.