Here are some Historical Romance writers that I like. The settings are in England unless otherwise noted. They are in alphabetical order (of course, I am a librarian after all). Disclaimer: For some of these I have only read one of their books, so they may have other books that are awful or inappropriate.
Joanna Barker (19th Century)
Julie Daines (19th Century)
Kimberley Duff (the two I read were set in India)
Sarah Eden (Regency and Victorian)
Georgette Heyer (Regency)
Kristi Ann Hunter (Regency and Victorian)
Josi Kilpack (19th Century and contemporary)
Sarah Ladd (19th Century)
Kim Vogel Sawyer (US history)
Helen Simonson (WWI and contemporary)
Anneka Walker (both historical and contemporary)
Roseanna White (WWI and WWII)
Karen Witemeyer (Western American)