I've always thought the drawings of Brit illustrator RONALD SEARLE had a profound influence on the design of the BRIGANDS in THIEF.
The Brigands were largely designed by Corny Cole, who might have been influenced by Searle also. Very similar style.
Searle designed and animated feature called Dick Deadeye, animated by Bill Melendez & based on the operas of Gilbert & Sullivan.
Searle's drawings of the pirates look similar to the brigands ... and, this being based on Gilbert and Sullivan, features the Princess Yumyum from the Mikado, and an evil sorcerer.
Wonder if it's available anywhere. It was quietly released on video in 1991 by a small company ...
EDIT: Got it ...
http://www.buyindies.com/listings/1/0/FCTS-10433.html
Won't pay full price for it, but I am curious to see it.