Born in Kinglass, he left Kinawley School at the age of 14 as so many of his generation had, to work on the family farm.
But he took up his first job in 1937 as a boiler man in Tiravalley Creamery for 18 shillings at week.
Through evening classes he began educating himself and eventually won his certificate as Creamery Manager.
He played football with his native Kinawley team in the late 1930's and early 1940's until he went to manage a creamery in Downpatrick.
He then joined the Ministry of Agriculture in 1945, being promoted to Deputy Chief of Fisheries and wrote his first published book, as a guide to "Angling Over the Border in Ireland."
He continued his education, obtaining a B.A. degree and at the age of 73, received his MSc in Irish anthropology and political science.
He worked on a voluntary basis with the Marriage Advisory Council and after 18 years, became Northern Ireland Administration Officer, writing a book on the subject entitled, "Like Ministering to Like," which was published by Columba Press.
He was predeceased by his wife, Rose; his son Philip of four years, his parents, James and Theresa; brothers, Dermot and Kevin and sister, Maggie.
Mr. Leonard is survived by his daughters, Dympna and Celine and by sons, Jack, Jim, Colum, Neill, Connor and Aiden.
He also leaves sisters, Ellen, Nora, Moira, Berthan and brothers, Sean and Aiden as well as his sister-in-law, Phyllis.
Following his funeral Mass, the burial took place in Milltown Cemetery, Belfast, where he was laid to rest with his wife and son.