Matilda Ridout was born to a prominent family in Toronto, Canada. Little is known about her early life and education. In 1865, she married James David Edgar, a lawyer and politician, with whom she had nine children. Her literary career began when she was in her mid-40s, after most of her children were grown. Her first work was an edited collection of old family letters in her possession entitled Ten years of Upper Canada in Peace and War, 1805–1815 (1890). Her second book, a biography of Sir Isaac Brock, was published in 1904. Her third and final book, A Colonial Governor in Maryland: Horatio Sharpe and His Times, 1753–1773 (1912), was based on documents and letters from his secretary John Ridout, one of her ancesters. She became Lady Edgar when her husband was knighted by Queen Victoria in 1898. She was involved in numerous philanthropic efforts and served as president of the Women’s Canadian Historical Society of Toronto. After 1900, she became more involved in advocating the rights of women to higher education, to work, to vote, and to control their own property.