Total War: Warhammer III Immortal Empires has official been launched this month, with Patch Notes 2.4.0 update. It has been on beta stage since last year, but now it should be available to everyone.
Total War: Warhammer III has previously only featured it's own campaigns and not connect it's new factions (Grand Cathay, Ogres and different Chaos hosts) to other realms. Until now. Personally I think this is the most exiting update, finally, on Total War: Warhammer -series, as it now expands the battlefield to almost entire Warhammer World (World-That-Was). Why did I say almost? Well, it seems that Ind, Khuresh and Nippon are not available, but we still should be able to sail and fight around the Warhammer World nicely.
During the last summer they already gave us map of the game world. This Total War: Warhammer III - The Immortal Empires Map -link will take you to that blog page on the official blog.
See more info from official Total War Twitter and from the official Total War Blog.