You are using an out of date browser. It may not display this or other websites correctly. You should upgrade or use an alternative browser.
alternatehistory.com
Your Challenge: have some way for the region of Anatolia to be a majortity slavic speaking area to the current day. In OTL, Byzantine emperors occasionally settled Slavic peoples in depopulated parts of the region to supply farmers and troops, but they were all eventually aculturized (certainly after the Turkish incursions). In the ATL, however, Anatolia becomes, and remains, a Slavic region to the present day.
Go!
P.s. I know that this AHC might require the eventual collapse of the Byzantines, which goes against many of the well known biases of this group ... but oh well