Susanna Gregory is the pseudonym of Elizabeth Cruwys, a Cambridge academic who was previously a coroner's officer. She writes detective fiction, and is noted for her series of mediaeval mysteries featuring Matthew Bartholomew, a teacher of medicine and investigator of murders in 14th-century Cambridge.

These books may have some aspects in common with the Ellis Peters Cadfael series, the mediaeval adventures of a highly intelligent Benedictine monk and herbalist who came to the Benedictine order late in an eventful life, bringing with him considerable secular experience and wisdom combined with a deal of native wit. This sets him apart from his comparatively innocent and naíve monastic brethren. His activities, both as a monk and a healer, embroil him in a series of mysterious crimes, both secular and monastic, and he enthusiastically assumes the róle of an amateur sleuth. Sceptical of superstition, he is somewhat ahead of his time, and much accurate historical detail is woven into the adventures. But there any resemblance to the comparatively warm-hearted Cadfael series ends: the tone and subject matter of the Gregory novels is far darker and does not shrink from portraying the harsh realities of life in the Middle Ages. The first in the series, A Plague on Both Your Houses is set against the ravages of the Black Death and subsequent novels take much of their subject matter from the attempts of society to recover from this disaster.

These novels bear the marks of much detailed research into mediaeval conditions - many of the supporting characters have names taken from the documentation of the time, referenced at the end of each book - and bring vividly to life the all-pervading squalor of living conditions in England during the Middle Ages. The deep-rooted and pervasive practice of traditional leechcraft as it contrasts with the dawning science of evidence-based medicine is a common bone of contention between Matthew and the students he teaches at Michaelhouse College (now part of Trinity College, Cambridge), whilst the conflict between the students of Cambridge and the townsfolk continually threatens to escalate into violence.

Another series of books, set just after the Restoration of Charles II and featuring Thomas Chaloner, detective and former spy, began with A Conspiracy of Violence published in January 2006, and continues with The Body in the Thames, due to be published in hardback edition January 2011.

This author page uses material from the Wikipedia article "Susanna Gregory", which is released under the Creative Commons Attribution-Share-Alike License 3.0