Mary Susannah Edgar was a Canadian author born on May 23, 1889. She is the author of several books, one-act plays and hymns, the most famous of them being God Who Touchest Earth with Beauty which has been translated into several languages and placed in Hymnals around the world.
She was the daughter of Joseph Edgar and Mary Little, from Sundridge, Ontario. In 1922 she opened a girls' camp near Sundridge on Lake Bernard, called Glen Bernard. Mary Edgar continued as the camp's director until her retirement in 1956.
Her life was devoted to working with girls and camping through many local, provincial and national organizations. She was the author of many books, plays and hymns - One such hymn is "O God of All the Many Lands".