Sir Arthur William Hill was born on 11 October 1875, the only son of Daniel Hill. Daniel Hill was a keen amateur horticulturalist and inspired his son from an early age to learn sound practical knowledge about gardening.
Hill attended Marlborough School from 1890 until 1894. It was at school that Hill began to take an active interest in field botany, inspired by his teacher [who was an amateur naturalist] Edward Meyrick. Hill later talked of the Marlborough Downs as the place where he first found orchids to examine. Hill showed his appreciation to the College by bequeathing them money.
From Marlborough School Hill continued his education at Kings College Cambridge in October 1894 on an award. His success in gaining the award was due to an appeal from Marlborough School based on his botanical knowledge, enthusiasm and promise. At Cambridge Hill studied Natural Sciences, for which he obtained a 1st in 1897. Hill continued to study at Cambridge but specialised in Botany and received a 1st in 1898. At this time the Chair of Botany was Henry Marshall Ward who had a great influence on Hill; Ward introduced him to Walter Gardiner [Cambridge lecturer until 1898]. Gardiner invited Hill to collaborate with him on research on plant histology for the Royal Society. This led to Hill being offered a post at Cambridge University as a Demonstrator in Botany in 1899. Hill was successful in his post and was awarded a fellowship in 1901, a lectureship in 1904 and the position of Dean of Kings College in 1907. As a lecturer he contributed much through his travels as he would return to Cambridge and describe the flora and fauna he had observed in its natural ecosystem. He helped to modernise the Botany School through his use of field trips, which took students out of the classroom to the plants in their natural environment. This achievement was acknowledged by Kings College in 1932 when he was granted an honorary fellowship.
In 1907 Hill left Cambridge to become the Assistant Director of Royal Botanic Gardens, Kew to the then Director Sir David Prain. Prain wrote that he chose Hill because of his travelling experiences [especially Hill's trip to the Andes which Hill financed himself], his businesslike mind and ability to work at any level. One of Hill's prime duties as Assistant Director was to attend meetings and trips to Imperial countries at the government's behest. Hill was very interested in the spread of knowledge and relished these trips, where he could gather specimens and in return offer advice to the host nations. Thus, under him the Royal Botanic Gardens, Kew developed its worldwide network of associates. He was also concerned that the Royal Botanic Gardens, Kew should develop its research side and improve in everyway possible.
In 1922 Prain retired leaving Hill to take over the Directorship of the Royal Botanic Gardens, Kew. Hill took full advantage of the opportunities offered to the Gardens by the British Empire and he successfully campaigned for the government to view Kew as a national asset that could be used to improve colonial relationships. Hill was concerned that the Royal Botanic Gardens, Kew should continue and extend its economic links within the Empire. For example, he created a greenhouse in which bananas on route to Jamaica could be quarantined in. Hill's commitment to commercial activities of this nature led the government to ask the Royal Botanic Gardens, Kew in 1931 to officially disseminate information on economic plants and their sources around the Empire. This led to the first inventory of plants in the British Empire. Hill was also much concerned with the Gardens on a domestic scale and under his guidance the number of plants that were exhibited was increased. He was a keen amateur landscape gardener and had a tremendous knowledge of plants which he used to enrich the Gardens as a visitor attraction. He was especially keen to see plants growing in as natural and beautiful a setting as possible and so changes were made to planting methods. Hill toured the gardens every morning and would order any changes he felt necessary to enhance artistic effect. Major alterations included: a new vista to the lake, the extension of the rock garden and the improvement of the avenue from the lake to the pagoda. In addition to this, Hill constructed the Sherman Hoyt Cactus House in 1935. Perhaps most significantly though, was Hill's extension in 1930 of the Herbarium so that scientific study could be extended into new areas.
Much of Hill's horticultural and botanical knowledge was informed by his travels abroad. On his travels Hill would collect material for study. Thus, he obtained grants from the Empire Marketing Board from 1927 onwards that allowed him to travel more than any other Director before him.
Sir Arthur William Hill died in the Deer Park in Richmond on 3 November 1941. His death is recorded by a number of obituaries all of which lament the passing of Britain's most accomplished botanist.