After medical school, he was a House Officer at the
Royal Victoria Infirmary in Newcastle where one of his instructors was the English surgeon,
Grey Turner. He passed the Master of Surgery examination, M.S. in 1944. He was elected a Fellow of the
Royal College of Surgeons of Edinburgh in October 1944 and overcoming institutional barriers, he became the first African and the first black person to be elected a Fellow of
Royal College of Surgeons of England. He opened a private Genera Practice in Newcastle and concurrently served on Colonial Office advisory committees dedicated to medical education and social services in West Africa. He toured Anglophone West Africa (Gambia, Sierra Leone, the Gold Coast and Nigeria) during March to September 1945, as a member of the Colonial Office Advisory Committee for the Welfare of Colonial Peoples. After the
NHS was established in 1948, he opted for a career in surgery and passed his examinations in ophthalmology in 1950 and obtained a Diploma in Ophthalmic Medicine and Surgery (DOMS). He then moved his General Practice to Nottingham. Due to discrimination in the West African Medical Service, Wellesley-Cole mainly practised in the
United Kingdom, although he did also practice in
Ibadan, Nigeria, and in his natal homeland of Sierra Leone. In 1961, he was appointed by the Nigerian Civil Service as a senior surgical specialist consultant in Western Nigeria. Following Sierra Leone's Independence on 27 April 1961, then Prime Minister
Milton Margai offered Wellesley-Cole the position of senior medical officer and in 1964, he became a Consultant Surgeon of the Government of Sierra Leone. In 1971, he became the Director of Clinical Studies in Sierra Leone. Wellesley Cole lost his British nationality status and by extension, his British passport which was eventually restored in 1981/82. He was however able to return to England in 1974. He had earlier been invited to become a Justice of the Peace in 1961, the first time this invitation had been extended to a black African in Britain. ==Activism==