Well NRPs can be from what I've seen. Stat based. I.E DnD style with numbers and all that. Or story based which is what Aaron is planning. And in that particular case you can ask to be either a character or perhaps faction? You'd have to ask Aaron about that but those seem the likely options. 

In any case in a NRP you play a Nation with hundreds under your command. You don't need to write for every single character that could possibly be. But you'll be doing it more so in groups. Move X number of troops. Have X number of Farmers do Y. And so on. With your Leader character controlling the action.