The son and heir of an Angus laird, Aikman sold his estates to finance his training as a painter. He studied with Sir John de Medina in Edinburgh before travelling to London in 1704. In 1707 he left for Italy, where he may have worked with Carlo Maratta. He also visited Turkey. Aikman returned to Edinburgh in 1711 after Medina's death and became the leading portrait painter in Scotland. By 1723, in search of new commissions and wider acclaim, Aikman moved to London. The Scottish nobility resident in London after the Act of Union of 1707 formed a large part of his clientele but he was also part of Lord Burlington's circle.