Jon Linn Breen was born on November 8, 1943, to Frank William Breen and Margaret Wolfe Breen. His parents’ professions may have influenced his own choice of profession and his love of scholarship: His father was a librarian and his mother a teacher. Breen’s college years were spent in California, where he received a bachelor’s degree from Pepperdine College (now University) in 1965. He then attended the University of Southern California, where in 1966 he completed an master’s degree in library science, a profession he would never completely abandon. During these years he was also a sports broadcaster for a radio station in Los Angeles. An interest in sports continues to be one of Breen’s major avocations and has influenced his writing.
After serving in the military from 1967 to 1969, including a year in Vietnam, Breen returned to library work. He served at several educational institutions in California before becoming the head reference librarian at California State College (now University), Dominguez Hills, a position he held until 1975. He then took a position as the reference and collections development librarian at Rio Hondo Community College at Whittier, California. In 1970, he married Rita Gunson, a teacher, of Yorkshire, England. She has coedited with her husband a volume of novelettes.
Breen’s first short story appeared in Ellery Queen’s Mystery Magazine in 1966, when he was twenty-three years old. That first effort was followed by more short stories, reviews, reference works, critical biographies, essays, and three respected novels. By his own admission, Breen followed the ambitious goal of becoming what he calls an “all-rounder,” in the tradition of writers Anthony Boucher, Julian Symons, and H. R. F. Keating. The goal has motivated him to achieve success in diverse areas of research and literature within the mystery and detective genre.