Gear was born in Methil in the south-east of Fife, Scotland, the son of Janet Gear (1886-1955) and Porteous Gear (1881-1965), a coal miner. At Buckhaven High School he won the Dux Arts Medal (1932), and studied at Edinburgh College of Art from 1932 to 1936, where fellow students included Wilhelmina Barns-Graham and Margaret Mellis.
He first exhibited in 1934 with the Royal Scottish Academy and Society of Scottish Artists, and his postgraduate scholarship (1936–37) included History of Art studies with Professor David Talbot Rice at Edinburgh University.
Awarded a travelling scholarship (1937–38), Gear visited France, Italy, Yugoslavia, Albania, Greece and Turkey. This trip included a stay in Paris studying with Fernand Léger. At summer school in Arbroath (1938) he met Robert Colquhoun and Robert MacBryde. A brief interest in Surrealism led him to exhibit with the New Era Group in Edinburgh in 1939.
Called up for military service in 1940, and commissioned 2nd Lieutenant in 1941, during the Second World War Gear served with the Royal Corps of Signals. He met Merlyn Evans in Durban, en route to his first posting in the Middle East. Gear subsequently served in Egypt, Palestine, Syria and Cyprus, before participating in the Allied invasion of Italy, where in Siena and Florence he held his first solo exhibitions in 1944. After VE Day he worked for the Monuments, Fine Arts and Archives section (MFAA) of the Allied Control Commission, with responsibility for securing art works in Lower Saxony in the British Zone of occupied postwar Germany. During his travels through Europe he also worked to promote local artists suffering from wartime deprivations, including Karl Otto Götz.
Between 1947 and 1950 Gear lived and worked in Paris, where he met Eduardo Paolozzi, Alan Davie, Stephen Gilbert and many of the leading post-war generation of Parisian artists including Atlan, Da Silva, De Stael, Dubuffet, Hartung, Mathieu, Pignon, Poliakoff, Schoffer, Singier, Soulages and Zadkine. In 1948 he held his first Paris and London solo exhibitions, and visited Terry Frost, Patrick Heron, Roger Hilton, Peter Lanyon and Bryan Winter in St Ives. After meeting Appel, Constant, Corneille, and Jorn, he joined and exhibited with the North European avant-garde CoBrA art group. in Amsterdam during 1949. That year he also co-exhibited with Jackson Pollock in New York, married an American citizen, Charlotte Chertok (1920–88), and their son David was born. Whilst holidaying in Brittany in 1950, he was visited by William Scott.
Later that year William Gear moved with his family to England (Loosley Row, Buckinghamshire), and in response to an Arts Council invitation to produce a work for its “Sixty Paintings for ’51” exhibition, he painted “Autumn Landscape”, now in the Laing Art Gallery, Newcastle. When the work was awarded a Festival of Britain purchase prize in 1951, the result was a public furore. Following a further move to the nearby Speen Farm (Flowers Bottom, Buckinghamshire), his son Robert was born the same year.
The following year he was amongst the pioneers in Britain to produce prints using the silk screen technique. He moved to Littlebourne in Kent (1953), was elected a member of the London Group, and began receiving commissions for fabric and wallpaper designs, producing about 100 over the following nine years. He was curator of the Towner Gallery in Eastbourne from 1958 to 1964, and then head of the Faculty of Fine Art at Birmingham College of Art, a post from which he retired in 1975. He became a member of the Royal Birmingham society of artists in 1966, and was Guest Lecturer at the National Gallery of Victoria, Melbourne, and the University of Western Australia, Perth (1966/67).
In 1967 Gear received the David Cargill Award from the Glasgow Institute of Fine Arts, was appointed to the Fine Art Panel of the National Council for Diplomas in Art and Design in 1968, elected FRSA in 1971, and awarded the Lorne Fellowship in 1975. That year he also retired from his Fine Art post, which by then was encompassed within Birmingham Polytechnic.
A touring exhibition (Paris, Chalon, and Rennes) of CoBrA artists’ work during 1982/83 heralded a revival of interest in the movement (1948–51). Over the next decade he participated in group CoBrA exhibitions in several countries, and also held solo shows of his CoBrA period works in London (1987 and 1989) and Paris (1988). In 1994 he was awarded the Royal Academy’s Sir Howard Barker Scholarship, and an Honorary Doctorate by the University of Central England. The following year he attended the opening of the new CoBrA Museum in Amstelveen, Holland, and was elected a RA.
In 2015 to celebrate his centenary Towner Gallery Eastbourne held a major retrospective of his works - William Gear 1915 - 1997: The painter that Britain forgot.
He died on 27 February 1997 in Birmingham, a few days after returning from a trip to Hanover to receive the Leporello Prize from the government of Lower Saxony, to mark his work for "democratic art and artistic freedom".
- "Artist biography: William Gear". Tate. Retrieved 10 April 2016.
- Sidey, Tessa (10 March 1997). "Obituary: William Gear". The Independent. Retrieved 3 April 2011.
- Frances Spalding (1990). 20th Century Painters and Sculptors. Antique Collectors' Club. ISBN 1 85149 106 6.
- "William Gear". University of Chichester. Retrieved 3 April 2011.
- Cook, Rachel (19 July 2015). "William Gear: the painter that Britain forgot". The Observer. Retrieved 16 September 2015.
- McEwen, John. William Gear. Aldershot: Lund Humphreys, 2003.
- Lambirth, Andrew. William Gear. Bristol: Sansom and Company, 2015