I picked up some books on ancient Persia and Zoroastrianism in the library further research into one of the important lands of Ygg. (So far, I have been working with Mary Boyce's Zoroastrians: Their Religious Beliefs and Practices.) Though Norse mythology was my initial inspiration, and the Northern realm is where I planned on starting out with PCs, Aryanistan, drawing inspiration from central Asia and Iran, is the largest empire in Ygg. Below is a C/C table on the two great religions of Aryanistan, the first which has the broadest popularity and the second which is the royal patronage and popular with ambitious nobles. Some of the ideas are firmer than others, but I liked the direction that it taking as weave game elements and historical elements into this proud, though conflict, imperial behemoth.
May the winds of inspiration blow upon you, this Mythopoeic Monday!