To emphasize a point under discussion, E.J. Watson once shot the mustache off a man named Brewer. So testifies writer Peter Matthiessen in Killing Mister Watson, the first of three dense, fascinating novels centering on a turn-of-the-century Florida cane planter, brawler and gunman who was shot to death in 1910 by a posse of townsmen.
The posse's makeup appears to have shifted over the years, with some members denying knowledge and some non-participants pinning ribbons of legend to their chest and claiming to have been among the shooters. Beyond these scraps of fact, clear sightings of old E.J. were brief. Was...