Powles was born in Cirencester, England, in January 1860, one of six children.^[2][3][4] His father was Rev. Henry C. Powles.^[5] Powles attended Oxford, where he studied Mathematics under Charles Lutwidge Dodgson, better known as Lewis Carroll, author of Alice in Wonderland.^[4] Powles gained his MA from there in 1898.^[2] Powles had formal art studies under Hubert von Herkomer,^[6] followed by studies in Munich.^[4]

Powles was elected a member of the Royal Society of British Artists^[7] in 1903.^[8] Powles travelled extensively throughout Europe, as well as to Canada.^[4] His works are in the Bushey Museum and Art Gallery, the Ferens Art Gallery, the National Trust, Lamb House,^[9] the Royal Welch Fusiliers Regimental Museum, the Victoria & Albert Museum,^[10][7] and the Royal Collection Trust.^[11] Powles is most well known for his watercolour landscapes, although he painted a number of oil portraits. Two of his watercolours were commissioned for the Library in Queen Mary's Doll House.^[12][13] In 1910, he painted English writer Henry James, who was Powles' neighbour and friend in Rye.^[9] Powles was also an Associate Member of the Society for Psychical Research, and was very interested in paranormal events.^{[14][15][16][17][18]} In a letter, he once said that he was "somewhat easily impressed by the thoughts of others".^[18]

He married Isabel Grace Wingfield on 21 January 1905.^[19] Their daughter, writer Viola Bayley, was born in 1911. Powles died in East Sussex in 1942.^[9]