John Capistran Cayer was born on 17 April 1900 in Capelton, Quebec. He began his studies at the Seraphic College in Trois-Rivieres in 1912. On 14 Aug 1919, Cayer took the habit and made his profession on 14 Aug 1920. He was ordained to the priesthood on 11 Jul 1926.
Not long after, in 1927, Cayer came to St. Anthony’s College in Edmonton, where he taught and served successively as Prefect, Rector, and Superior. He added a new wing to College in 1931.
From 1939-1941, Cayer studied Theology in Innsbruck, Austria. Upon his return to Canada, he taught at Regina Cleri Major Seminary in Regina from 1941-1945.
In 1945, he was appointed Commissary Provincial of the Franciscans in the west. Three years later, on 2 Aug 1948, he was elected by the Chapter to be Provincial of St. Joseph’s Province and was based in Montreal.
John Capistran Cayer was consecrated on 17 Sep 1949 as Bishop of Cissi and Vicar Apostolic of Egypt. He served in this role from 1949 until his death.
He died on 13 Apr 1978 and is buried in Alexandria, Egypt.