Born in Brighton, the son of the Rev. A. T. Gill, he studied at Chichester School of Art before being articled to the architect Douglas Caroe, 1900–03. During this period he attended evening classes in masonry at the Westminster Technical Institute and in lettering at the Central School of Arts and Crafts.
He began working as a letter cutter in 1903, taking apprentice-assistants shortly afterwards. Worked as a sculptor from 1910. His conversion to Roman Catholicism in 1914 was very important and he became a tertiary of the order of St Dominic five years later. Designed some of the most famous type-faces of the twentieth century for the Monotype Corporation. Settled in Ditchling 1907 and ran the St Dominic’s Press, until 1924; worked with the Golden Cockerell Press. Moved to Capel-y-Ffin in 1924 and then to High Wycombe in 1928. His most famous commissions include the Stations of the Cross, Westminster Cathedral, 1913–18; War Memorials for Leeds University and St Cuthbert’s Church, Bradford 1920-24; 'North, South and East Wind', London Transport, Headquarters, 55 Broadway, 1928; 'Prospero and Ariel', Broadcasting House 1929–31, and carvings for the Palestine Museum, Jerusalem, 1934 and for the League of Nations Palace, Geneva, 1935–38.
Gill held his first one-man exhibition at the Chenil Galleries 1911. He was a prolific writer and pampleteer on many subjects from Catholicism and morality to work, leisure and dress. Exhibited at the Royal Academy during the last few years of his life.