Between 1920 and 1926 Evans was the British vice-consul at New York City, and for another three years after that at Boston. In 1929, he was sent to Colón, Panama, remaining there until 1932, when he again returned to the United States. He subsequently spent five years as consul at Los Angeles, and after a period at the Foreign Office he returned to New York as consul general there, an appointment he held until 1950.
In 1951 Evans became under-secretary of state at the Foreign Office,[citation needed] and the following year he was appointed British ambassador to Israel,[2] having become minister there the previous year. This was immediately followed in 1954 by his appointment as ambassador to Argentina, a post he held for three years before retiring.
From 1957 to 1965, he was chairman of the Northern Ireland Development Council, and from 1962 and 1966 he also served as the agent for the Northern Ireland Government in Great Britain.