Morrison was born in Lithgow, New South Wales and graduated with an honours degree in economics from the University of Sydney in 1949. He was a diplomat in the Department of External Affairs from 1950 to 1969, with postings to London, Moscow, Washington, D.C., Bangkok and Kuala Lumpur. His posting to Moscow was terminated by the expulsion of the entire mission in 1954 as a result of the Petrov Affair. His posting to Malaysia was as Deputy High Commissioner. In 1958, he married Marty Hessell, an American citizen, in Bangkok.
