May Marshall Brown (nee Brown Robertson) was born in 1887, as the daughter of an Edinburgh wine merchant (William Robertson). Her artistic talents were the focus of her education. She studied at the Royal Institute in Edinburgh and the Edinburgh College of Art.
May exhibited at the Royal Scottish Academy, the Royal Scottish Society of Painters in Watercolours, the Glasgow Institute of Fine Art and the Scottish Society of Artists. She was elected to the Royal Scottish Society of Painters in Watercolours in 1936.
In 1912, May married artist William Marshall Brown RSA (some 24 years her elder). Many of her watercolours portray fishing villages, boats, harbours and those people that resided and frequented those places.