Since OGF's world history is often retroactive and spotty, why not use countries (and their wiki pages) that have been abandoned as sources of ancient history or 'lost civilizations'?
For instance, before Picard was removed, I speculated that some of their culture migrated across Tarephia into Drevet & Wustesonne (my territories). Just like in real-world history, civilizations rise and fall all the time. So, whomever claims what was Picard, they could either make references to the previous country in their history or forge their own backstory.