Glyn Warren Philpot's Head of a Negro sold for £302,500 ($448,305) in a sale of British and Irish art at Christie's London on March 19.
The piece achieved an increase of 1,412% on a £20,000 ($29,640) estimate.
Philpot (1884-1937) is best known for his portraits of notable people of his era, including Siegfried Sassoon and Oswald Mosley.
He was gay at a time when homosexuality was illegal and his work can be seen as explicitly political in its focus on the male form.
The present lot is one of a number of portraits depicting black men. It was painted in 1937, the year Philpot died.
Christopher Wood's Fishing Village, Cornwall (1926) proved another highlight. It sold for £218,500 ($323,817), an increase of 118.5% on a £100,000 ($148,200) estimate.
Wood produced some of his best work during his time in Cornwall. He wrote to his mother in 1926: "I know that my stay in St. Ives has been a great profit to me as I have at least learnt how to finish my work, which is the most… difficult part.
"I feel I have thought a lot and assimilated much and that now really I feel that I am an artist and couldn't ever have done anything else in my life, which is a great comfort to me."
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