This is it, the first DLC for Empires is out ...
Description of the content here:
https://www.matrixgames.com/game/field- ... 50-330-bce
I would also advise checking the awesome and instructive 'Nations Focus' on Persia, Sparta and Athens.:
Sparta
https://www.matrixgames.com/news/focus-faction-sparta
Athens
https://www.matrixgames.com/news/focus-faction-athens
Persia
https://www.matrixgames.com/news/focus-faction-persia