The current world
I´m pretty sure that you can´t take the Mongols and there aren´t any Ottomans yet. The big red blob over Turkey is Muscovite which is a permanent NPC (cant be taken). The Light Blue nation in Georgia is Georgia, the yellow one is Syria (christian) and the Green one is Sumer(taken). Not very ottomanish.
The Rules
Important!
The player nations
These nations are already taken.
NPC nations
Since there isn´t much room for a new civ i suggest taking one of these.
Old World map with nation names
Much has changed but some nations are still the same.
These are some of the new nations in europe.
In France: Brittany, Andorra, Lorraine, and Provence.
In Iberia: Toledo, Andalusia, and Douro.
In Italy: Naples and Calabria.
In Central Europe: Holland(taken), Hamburg, Germany, Prussia(taken), Switzerland(taken), and Venice
In Greece: Sparta(taken), Athen, Macedonia, Thrace, Byzantium(taken) and Georgia