Colonel James Henry Bowker (23 August 1825 – 27 October 1900), was a South African naturalist and soldier. He was co-author with Roland Trimen of South African Butterflies (1887–89; 3 vols.).
He was the ninth and youngest son of Miles Bowker (born c.1758 at Deckham's Hall, Gateshead, Durham), and Anna Maria Mitford, (born 1782 in Mitford, Northumberland, died 8 July 1868 at Tharfield), both 1820 Settlers. James Henry Bowker was born on a farm known as Olive Burn, on the Klein Monden River, north of Port Kowie. He was actually baptised as William Henry Bowker on the 17 December 1825, but was known as James Henry Bowker.
He was appointed inspector in 1855 of the Frontier Armed and Mounted Police (F.A.M.P.), later succeeding Sir Walter Currie as Commandant. He also acted as High Commissioner of Basutoland. During the Seventh and Eighth Kaffir Wars he was promoted to Colonel. He took part in the suppression of the Kat River Rebellion and the capture of Fort Armstrong in 1846-7, for which he earned a medal and clasp. For a while he was Chief Commissioner on the diamond fields of Griqualand West.
He was a knowledgeable naturalist and collected large numbers of butterflies which he then supplied to museums. His older sister Mary Elizabeth Bowker, who had married Frederick William Barber, was a noted botanist and entomologist as well as being a painter and author. She corresponded regularly with Joseph Hooker, William Hooker and Charles Darwin. James Henry Bowker never married.
Fort Bowker, built around 1860 to keep the Gcaleka north of the Mbashe River, was named after him, and there is still a road named after him in Maseru, the capital of Lesotho (formerly Basutoland).