Born 14 September 1863 in West Brompton, London, of parents from Alton, Hampshire, Allen was for many years Director of the Farnham School of Art in Surrey.
He produced several thousand watercolours, chalk and pencil sketches mainly of the landscapes, traditions and people of West Surrey and North-east Hampshire.
In this he was helped by fellow Farnham resident and friend George Sturt, whose writings reflect Allen's approach to the recording of rural life and change.
[2] In the 1880s, the depiction of life and work in the countryside was subject to two very different approaches, the traditional rural romanticism/sentimentality - thatched cottages with roses around the door and contented happy harvest scenes (e.g. Myles Birkett Foster), and that of social realism - recording child labour and exploitation, agricultural depression, bad weather, hard work and hard labour (e.g. Sir George Clausen).
By the time Allen started recording the countryside around Farnham in the 1890s, Britain was in the grip of a severe agricultural depression which continued until the late 1930s, mirroring his artistic output.
Allen gave private wood carving lessons to Harold Falkner who later became an architect and leading light in the preservation of Georgian Farnham.