Sir Robert Thorne Coryndon, CMG (1911), KCMG (1919), was born in South Africa on the 2 April 1870. He was educated in South Africa at St. Andrew's College, Grahamstown, and in England at Cheltenham College.

It was intended that Coryndon should follow his father's profession of the law, and with that object he returned to South Africa in 1889, at the age of 19, in order to serve his articles with his uncle's firm, Caldecott and Bell of Kimberley. However, in the same year Coryndon left office-work and joined the Bechuanaland Border Police under the British South Africa Company. In the following year became a member of the Pioneer Force occupying Mashonaland. He served in campaigns in Matabeleland in 1893 and 1896 and formed part of the band of young South Africans known as Rhodes' "Lambs" or "Apostles".

In 1896 Coryndon became private secretary to Cecil Rhodes; he acted in that capacity during the Parliamentary Inquiry into the Jameson Raid (1896). However, although he always supported Rhodes' ideals he did not care for the position and in the following summer Rhodes sent him to represent the British South Africa Company in Barotseland. Shortly afterwards Coryndon took over the administration of North Western Rhodesia, in collaboration with the Barotse chief, Lewanika, and remained there until 1907. Coryndon was then transferred to Swaziland where, as Resident Commissioner, he was chairman of the Southern Rhodesian Native Reserves Commission of 1914-1915.

In 1916 Coryndon was appointed Resident Commissioner in Basutoland and a year later was appointed Governor and Commander-in-Chief of Uganda; he assumed the government in 1918. He was appointed to his final post in 1922 as Governor and Commander-in-Chief of Kenya and High Commissioner of Zanzibar. Sir Coryndon died in Nairobi on the 10 February 1925.