Here is the first section about Istar and the other Baklunish Gods
Istus B Fate, Destiny N FThe Baklunish religion revolves around the acceptance of fate. That no man may escape his fate. Fate is personified, by the Baklunish, as the goddess Istus, the lady of destiny and fate. This focus on Istus causes many Baklunish to be fatalistic about life. Many travellers will attest that most common phrase among Baklunish folks is, "It is the will of Istus". This fatalism often causes the Baklunish to take more risks and to be more militant than the other cultures in Flaness.
Zuoken BC Physical and Mental Mastery N M
Xan_Yae BC Twilight,Shadows,Stealth, N F
Geshtai BC Lakes, Rivers, Wells N F
Istus became the dominant religion of the Baklunish after the Invoked Devastation. The destruction that was caused, and the struggle to rebuild against the magical chaos that persisted after the Invoked Devastation caused the Baklunish to embrace Istus.
Many of the Baklunish do not actively peruses worship or service with her. This is because many Baklunish view her often as a cruel and uncaring goddess. This also causes an attitude which makes many Baklunish appear not as religious to outsiders. However anyone born in Baklunish culture is always concerned with his fate and will work to ensure his fortune. Truly, to one born in Baklunish lands, no one escapes the will of Istus.
One of the other effects of Istus's influence on Baklunish society is the flourishing of scholarly arts. Those who study the scholarly arts and the ways of magic are in great demand. The rulers and merchants come to them seeking knowledge of what future that Istus has for them.
Istus does have clerics and 80% of these are female. Society in Baklunish lands is traditionally male dominated. This stems from the earliest days and was a part of Baklunish culture even before the Invoked Devastation. Women are regulated to a lower social class than their male counterparts and are given less rights. However Istus would accept any into her service and many women joined. Service to Istus became even more popular among women when it was discovered that Istus treated all who served equally and many women were in positions of power. Men feared Istus for her power over their fates and thus followed the dictates of her priests even if they were women.
Istus is not the only power worshiped in Baklunish society, other arose when men desired to follow others to gain control over their fates. Zuoken is a demi-power that preaches that if one controls his body and mind, then he will gain control over his fate. The followers of Zuoken are called the Followers of the Way. The Followers of the Way made their appearance about 200 years ago in Baklunish Society. They developed methods and techniques that lead to the development of the unarmed martial arts. Also there are rumors that their discipline of the mind is becoming so great that they are able to affect the world and others with the power of their mind alone.
Xan Yae is an older minor power that appeared over one thousand years ago. The followers of Xan Ye believe that all men are predestined by fate. She preaches that only way to deal with fate is to laugh at her face and take as much of life as one can. Xan Yae is the patron of thieves throughout Baklunish Society.
Geshtei is the only power to survive the coming of Istus. Geshtei was one of the myriad powers that the Baklunish worshiped before the Invoked Devastation. These powers were associated with places and elemental forces. Geshtei is the patron of Lakes, Rivers, and Wells, and his clerics protect oasis wells, local lakes, and rivers from those who wish to possess or pollute them. Geshtei survived because much of the southern Baklunish lands are in areas where there is very little water. To this day Baklunish caravan masters and the Paynim nomads give thanks to Geshtei when they reach an Oasis.
The Tiger and Wolf Nomads the old Baklunish survived. The shamans among the nomads protect the tribe from the spirits and try to enlist their aid when the tribe needs help. During their migration the shamans of the Tiger Nomads made a great sacrifice to the spirit of the Tigers to protect their people for all times. The shamans of Wolf Nomads also performed a great sacrifice, but to the spirit of the Wolves. Today both tribes greatly honor their guardian spirit.
The rest you can read here. Warning this is not well edited I wrote this around 1989. This was written before I was aware of the later Greyhawk products like Fate of Istus.