Recommended Alternate History Authors

As it so happens, there was an observation from another user that Harry Turtledove has quite possibly been rendered obsolete due to not being the biggest "entry point" into the alternate history genre. I have to ask though, who all would you guys recommend as far as AH series goes?

The ones I'm familiar with are Turtledove (obviously), S.M. Stirling (Whether due to the Draka, Emberverse, or Nantucket), and Harry Harrison's dismal Stars and Stripes Forever. But does anyone else have any recommendations?
 
I would certainly point to the work of writers who would be considered more accessible.

For comics go to Warren Ellis, Grant Morrison, Jonathan Hickman, and Alan Moore. Grant Morrison has almost single-handedly brought about the modern DC multiverse, check out Multiversity,. Alan Moore helped create The League of Extraordinary Gentlemen and The Watchmen, both of which served to bring about mainstream awareness of the genre,...

For mainstream authors there is George R.R. Martin, Michael Chabon, Robert Harris, and Philip K. Dick. While they only briefly dabbled in the genre, consider that the quality is unquestionable...
 
Alternate history is a strange genre in that everyone who isn't making historical fiction that tries to be as exact as possible technically counts as "alternate history". So, do you want alternate history as a genre (the divergences are the central point) or alternate history as a setting (there's a divergent setting that serves as the foundation for a mystery/action/whatever story?)
 
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