Brady was born in Allegheny, Pennsylvania, and graduated from the U.S. Naval Academy in 1883. In 1889, he was ordained a deacon in the Episcopal church, and was ordained a priest in 1890. His first wife was Clarissa Guthrie, who died in 1890. His second wife was Mary Barrett. Brady's first major book, For Love of Country, whilst telling the story of a fictitious John Seymour, was actually based in part on the true heroics of Nicholas Biddle, one of the first five captains of the fledgling Continental Navy. Brady was also famous for his views of feminism and Women's suffrage, he preached many anti-suffrage sermons and described women voters as "an insult to God". In 1914 Brady began working as a screenwriter at Vitagraph Company of America.

FATE OF THE CASTAWAYS: My first determination was to seek a supply of breadfruit and water at Tofoa, and afterwards to sail for Tongataboo, and there risk a solicitation to Poulaho, the king, to equip our boat, and grant us a supply of water and provisions, so as to enable us to reach the East Indies.