Hubert William ("Pop") James received his schooling at Berkhamsted, near the town of his birth, and in 1900 came to the Cape Colony to recover from tuberculosis. He settled on a farm near Cookhouse, Eastern Cape, but by 1919 resided on the farm Klipkraal, near Tarkastad. Later he lived at or near Somerset East, Halesowen and Cradock, all in the Eastern Cape. During the nineteen-thirties he built concrete reservoirs of his own design for farmers, and later managed the affairs in Cradock of what later became the Allied Building Society. After retiring in 1964 he settled in Salisbury, Southern Rhodesia (now Harare, Zimbabwe) to live with his oldest son, Ronald.
James was interested in birds from an early age and developed into a serious student of their nests and eggs in particular. By 1919 he was a member of the South African Biological Society. His observations of birds were reported in "Notes on birds occurring in the Cradock and Tarkastad districts, Cape Province, with nesting dates" (South African Journal of Natural History, 1921, Vol. 3(1), pp. 174-199), "Further notes on the birds of the Cradock District" (Ibid, 1929, Vol. 6(4), pp. 281-286), and in an excellent paper, with many natural history observations, on "Birds observed in the Somerset East district, Cape Province, Union of South Africa" (The Ibis, 1925, Vol. 67(3), pp. 621-648). He was the first to describe the nest and eggs of Stenostira scita (the Fairy Flycatcher; The Ibis, 1922) and that same year published a paper on repeat layings in the American Journal of the Museum of Comparative Oology. Over the years he built up a documented collection of eggs, exchanged specimens with other oologists around the world, and contributed many technical articles on the eggs and nests of particularly warblers to the Oologists Record during the nineteen-twenties and thirties. The Cradock form of the Grey-backed Cisticola, Cisticola subruficapilla jamesi, was named in his honour by Admiral Hubert Lynes in 1930.
After 1930 James had less time to spend on his scientific activities, but his interest revived after his retirement. In Zimbabwe he became honorary keeper of oology at the Queen Victoria Museum in Harare. There he reorganised his egg collection and combined it with the collections of the National Museums of Zimbabwe to form what was regarded as the best birds egg collection in Africa. This work led to the publication of his Catalogue of the birds eggs in the National Museums of Rhodesia (1970). He also published (with R.K. Brooke) two further papers in The Ostrich, based on his eggs and notes relating to the valley of the Great Fish River in the Eastern Cape.
James was a short, slight man whose courtesy and enthusiasm for his work earned him much affection and respect.