America in the 1800s isn't quite the historical mystery hotbed as the same period in the country it bested in the War of Independence, but its unique spectacle of rapid social change and the lingering influence of its literary voices act in a parallel manner upon crime fiction chroniclers devoted to this side of the Atlantic.
Beginning in the 11th century, a less-fragmented Europe began to take shape, and what we now call medieval culture - in which literature and learning made a noticeable rebound - spread through much of the territory Rome had once dominated.
Imagine a world, if you will, where crime does not exist. A startling proposition that seems outlandish, but our imaginations, of course, need not be bounded by the rules and restrictions imposed by realism. It would be a world, one might suppose, where equality reigned, where the thought of violence was so alien that it need not be practiced.
Wambaugh's naturalistic portrait of the cop world turned 'Centurions' and 'The Blue Knight' (1972) into bestsellers, but his next two books made him relevant to a larger audience and to the next generation of crime writers.
'The Choirboys' is very much a product of its mid-1970s time, especially in its two-dimensional portrayals of cop groupies Ora Lee and Carolina Moon, but the energy of Wambaugh's newfound, blackly comedic voice is a revelation, a trap-door opening into all facets of a policeman's world.
Indeed, mysteries lead readers through an endless variety of subjects and settings; yet sometimes devotees of detection seek to be transported though another dimension as well: time.
The abundance of Roman historical mysteries contrasts with the surprising paucity of crime novels set in classical Greece.
The Cold War was over, presidential sex scandals superseded foreign concerns, and the American public was more interested in reading about fiendish serial killers, dependable mystery series protagonists, and any book thought to be in the vein of Bridget Jones and her abbreviation-happy diary.