Start with high-confidence non classifiable books, then narrow by subgenre or adjacent topics.
Victorian London
Liza Picard
Italy`s Sorrow
James Holland
Tail-end Charlies
John Nichol, Tony Rennell
Indian Summer
Alex Von Tunzelmann
Wolf Hall
Hilary Mantel
Smack
Melvin Burgess
Unexpected Light, an
Jason Elliot
Eagle of the Ninth, the
Rosemary Sutcliff
Lantern Bearers, the
Silver Branch, the
Good Hanging, a
Ian Rankin
Operation Napoleon
Arnaldur Indridason, George Guidall
How to Analyze People on Sight
Elsie Lincoln Benedict