Safavid Dynasty believed in one God and considered Muhammad was the successor of God whereas the other Islamic regions believed in one God. The Safavid Empire was reinforced by significant Shi'a warriors from the Ottoman armed force who had fled from mistreatment.
Step-by-step explanation:
Safavid Dynasty was the milestone that changed the religious belief in Muslim history. The other empires followed Sunni Islam believes only in one God who is everything and there would be no heir to the god.
The leader for their community should be selected by the community people via voting. Meanwhile, the Safavid's strongly believed that Muhammad (Founder of Islam) was the successful heir and the rest of the leaders were the direct lineage of Muhammad family.
They established Twelver theology(Spiritual belief) which was acceptable by most people Also, they spreaded them in order unified their empire.