William Simmonds was born in Istanbul, where his father was working as an architect, in 1876 .
In 1893 , after spending four years in his father's architecture office and attending evening classes at Windsor School of Art he began to study painting under Walter Crane at the Royal College of Art. He continued his training between 1899-1904 at the Royal Academy School, where he studied scenery painting, among other subjects. Between 1906-1910 he worked as an assistant to the American painter and illustrator Edwin Austen Abbey working on mural paintings among other commissions.
William married Eve Peart, the embroiderer, in 1912 and they moved from Wiltshire to London in 1914 . During the First World War, William worked as a precision draughtsman on, for example, tank design. It was during this time that he developed his interest in carving, often working with ivory.
In 1919 the Simmonds moved from London to Far Oakridge in the Cotswolds where they set up home and workshop. Here William worked on carvings and sculpture, sometimes painted, of animals and people in stone and wood, and sometimes using marble and alabaster. His life-long interest in theatricals resurfaced in the 1920's when he made his first puppet for a children's party and he continued, with Eve, to create puppet shows during the 1920's and 1930's . The Simmonds' puppet theatre was one of three established in England at that time, playing an annual season of three weeks at the Grafton Theatre, London and attending special performances at other venues including the Art Workers' Guild and at private parties. Eve made the puppets' costumes, mostly from fabric scraps, and she also provided musical accompaniment.
The Simmonds were fully integrated into the Cotswolds artistic community, exhibiting regularly in Campden, Painswick and Chelthenham. In 1960 the Simmonds moved to Oakridge Lynch. Forced to give up carving in wood due to arthritis William began pottery classes at Stroud School of Art. There was a retrospective of his work in Cheltenham in 1968 and he continued working up to his death later that year.