To sector24:
I don't remember details now (& am not sure about Mongol origins), but it's possible that curved sword existed in the region earlier. After all, ancient Persians had extensive contact with Greeks who DID use such (though closer to yataghan design)!
Certainly, swords from Stambul museum attributed to Mohammed the Prophet have straight long blades, relatively narrow. With their current hilts they are closer to 18-19th century cavalry broadsword than to scimitars as we know them.
Also, sabres are different weapons, with straighter blades, different balance & form of hilt guard. Polish ones are really inherited from Tartar mercenaries' curved swords, but about Hungarian ones I'm not sure. They could bring them with themselves from steppes or adapt some design of Balcanian curved sword...
And yes, they are thematic, so they would appear sooner rather than later, but from my point of view, not on baseline infantry (mostly spears) or non-archer cavalry (light lances - though it's a pity that the game doesn't allow for usage of different weapons by the same units, for Persian Pehlevans (Knights) were attributed to ride into combat "bearing 14 kinds of weapons" as a rule!
).
To Aezeal:
I don't think morale 9 is good idea, while cost is too low even if we take it into account (I still don't think that 11-12 stats are appropriate for commoners, m.b. just higher defense, which will get along nice with light encumbrance)... On description - if you would use word saif, it should be noted here somewhere that such is their name for curved sword. Or probably just use commonly known word scimitar. For commoner warrior of the period I would probably just use robes instead of body armor - thematic & cheap. Also, probably mounted troops should be cheaper than with others, in description it can be mentioned that they breed the best horses & so are able to field cavlry cheaper or somesuch.
On MA - I think nation name should become either Xanadu (though the poem about it actually refers to Khubilaj-khan, ruler of Mongolian dynasty, but it's known as a symbol of Eastern opulence...) or Khaleb (which was used in Persian tales as equivalent of "long time ago, in a galaxy far, far away"...
), with a subttitle of "Flower of Desert" or "City of 1001 delights". LA should probably be named either Magrib (which was usually used as land of origins of black sorcerers) or something like Sultanapur. What anybody think? Military engine I would send about tomorrow, I still need to think up some details, but it should include both light nomadic lancers and heavier troops of Turkish likeness (maybe the latter shouldn't get fireres?). Hashishiin, sure. Maybe some kind of infantry will begin to use halberd at the time...