Gerald Marks was born in London in 1921 and showed an early talent for painting and drawing. His studies at the Central School of Art (1938-41) were interrupted by service during the Second World War, then resumed from 1946-48. His work was featured in several group exhibitions from the late 1930s, including the London Group, the Redfern, Piccadilly and Leicester Galleries, and Warwick Arts Trust. In the 1940s and 50s, his work comprised mostly portrait studies and figure drawings and was deeply influenced by his tutor Bernard Meninsky. In the late 50s Marks adopted a more abstract style, showcased in his 1962 solo exhibition at London's Drian Gallery (established by emigre Halima Nalecz, 1957-c. 1990). He held further solo shows at Faroe Road Studios in 1988 and William Jackson Gallery in 1991. In 1980 he gained an Arts Council Major Purchase Award.
From 1948-61 he was a visiting lecturer at Camberwell School of Art, Morley College, Heatherley's School, South East Essex Technical College School of Art and the Workers' Educational Association. He taught full-time at Croydon College of Art from 1961-86 and was also a visiting tutor at Stourbridge School of Art. During this period he abandoned oils in favour of acrylics, also working on a larger scale and employing a more gestural handling. After retirement in 1986, he spent part of each year painting in the South of France, where he was particularly inspired by the wild landscapes of the Cevennes. His work is also held by the Arts Council and Warwick Arts Trust.