Margaret Frazer, born Gail Lynn Brown (November 26, 1946 – February 4, 2013), was an American historical novelist, best known for more than twenty historical mystery novels and a variety of short stories. The pen name was originally shared by Frazer and Mary Monica Pulver Kuhfeld in their collaboration on The Novice's Tale, the first of the Sister Frevisse books featuring the Benedictine nun Dame Frevisse. Their collaboration came to an end with The Murderer's Tale, the sixth book in the series. Starting with the Edgar Award-nominated The Prioress' Tale, the Margaret Frazer pen name was used exclusively by Gail Frazer. She also wrote the Player Joliffe mysteries, starring the medieval actor Joliffe.
Frazer was born and grew up in Kewanee, Illinois. An actress and member of the Society for Creative Anachronism, she lived and worked in Elk River, Minnesota. Frazer died February 4, 2013 from breast cancer, aged 66.
The first six Dame Frevisse mysteries were written as a collaborative effort between Frazer and Mary Monica Pulver Kuhfeld. The rest of the series was written by Gail Frazer alone. Frevisse is a nun at the small, fictional, 15th-century Oxfordshire convent of St. Frideswide's, with its ten (more or less) nuns; the neighboring village of Prior Byfield belongs partly to the priory and partly to Lord Lovell (an historical figure). Six of the novels are set entirely at the priory and/or village; in others Frevisse leaves the convent, either to accompany another nun on some family or convent business or on business of her own. Many of the novels have the quality of "English village" murder mysteries, in which we see at close hand the everyday material life (and the intellectual and spiritual life) of various classes of people and observe the tensions within and between them; but here, the "everyday" is of the 15th century, carefully researched. Some of the later novels are primarily historical novels, in which Frevisse serves as an observer of the well-documented events and characters which brought on the Wars of the Roses, though there is always a murder for her to solve.