I like alternate history, but I don’t have much of a head for real history, so when a plot relies mainly on small variations in a historic war, my eyes glaze over and I can’t tell what’s going on.
I have nothing against Harry Turtledove, I’ve just already read and enjoyed the books of his which sounded interesting.
Things I often like but are not required: Victorian/industrial settings. Modern settings. Politics and nation-building. BIG changes, especially the explicitly supernatural or alien. Focus more on institutions over personal relationships.
Books I’ve enjoyed (not all alt-hist): Turtledove’s Alpha and Omega, Through Darkest Europe, Worldwar/Colonization. Charles Stross’s Merchant Princes series. Frederic Rich‘s Christian Nation. Just about everything Michael Crichton wrote. Kim Stanley Robinson’s Mars trilogy. Peter Hamilton’s Commonwealth Saga and Salvation books.
by TBestIG