AU Developers - Please PM Knightmare or MechRat if you need board or permission changes
Just an admittedly quick browse over on sarna.net reveals this page which is quite informative. https://www.sarna.net/wiki/Nueva_Castile
Nueva Castille would translate simply via English to me as New Castille. This meant to me that it is a spaceborne successor to the Kingdom of Castile likely settled by Spainards. https://en.wikipedia.org/wiki/Kingdom_of_CastileSeems to be a theme of the Coreward proto-states of the Periphery to name yourself after an ancient empire of Earth. I'll do more research on a BattleTech basis and would be happy to chat about it with you as always.