Complex sentence: He went to Ceylon (later Sri Lanka) as High Commissioner in 1962, and in 1965 assumed the additional role of Britain's first ambassador to the Maldive Islands, after they had gained independence in July of that year.
Split into simpler sentences: He went to Ceylon (later Sri Lanka) as High Commissioner in 1962. Three years later, he assumed the additional role of Britain's first ambassador to the Maldive Islands, after they had gained independence in July of that year.