We have updated our Community Code of Conduct. Please read through the new rules for the forum that are an integral part of Paradox Interactive’s User Agreement.
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.
Oh, did you just start the game? Let it run a few days, it takes a while for the engine to decide they need to be named "The Cumans" due to being the cultural head of the cuman culture. Culture-based nomadic titles are dynamic.
That's without the DLC enabled. The devs gave the Cumans the title so they don't immediately collapse. However the setup is ahistorical and they shouldn't be united in 1066 or 1178.