Having completed the course there, he proceeded to India and received an emergency commission on 19 November 1944 as a second lieutenant in the 3rd Battalion of the Madras Regiment, the oldest in the country.

[4] Following his retirement from the Indian Army, he went directly back to Canada to take a BA and MA at the University of Western Ontario (Assumption College).

During this time, he developed a keen interest in Commonwealth affairs, which brought him back to Britain, where he acquired his doctorate from Cambridge University in 1955.

In these capacities, he was among the Earl Marshal's staff for the State Funeral of Sir Winston Churchill in 1965, the Investiture of the Prince of Wales in 1969, and was Gentleman Usher-in-Waiting to Pope John Paul II during his visit to the United Kingdom in 1982.

Swan also took a special interest in Saskatchewan, helping the province to obtain a full coat of arms from the Queen in 1986 and a new Great Seal in 1991.

[citation needed] Swan was appointed an Officer of the Order of St. John (OStJ) on 8 August 1972,[6] with promotions to Commander (CStJ) on 11 December 1975 and to Knight (KStJ) on 6 April 1976.

In 1957, Swan married Lady Hilda Susan Mary Northcote (born 23 July 1937 – died 4 December 1995), Serving Sister Most Venerable Order of St. John, Dame of Honour and Devotion Sovereign Military Order of Malta; Dame of Justice (SMO) of Constantine St. George; and President, St. John's Ambulance Society Suffolk.

Lady Hilda was the younger daughter of Henry Stafford Northcote, the 3rd Earl of Iddesleigh, and granddaughter of author Marie Adelaide Belloc Lowndes.