Originally posted by DJpannyflute:

Playing large true start location earth with barbarian clans mode. The barbarians convert to a city state but all the city states are named after american cities, they're like a grayed out color and the game doesn't recognize them as city states

I'm getting this same problem. They do not show up as city states that you can interact with, nor can I declare war on them.

its because you dont have enough colors for all the different city states and civ's. Downloading the prismatic color mod fixed it

For me downloading the prismatic mod only fixed the city state borders appearing transparent, but barbarian clans still converted to random American cities without me being able to interact with them. I found the issue is the "Only Leaders/Civs with TSL" option. For some reason when this option is selected the CivilizationType in PlayerConfigurations is always nil for all but the player Civ. It doesn't seem to affect normal gameplay (civs that spawn at the beginning), but when a barbarian camp converts to one of the civilizations in the RESERVED slot this bug appears.