First: The First Nicene Council
In 325 C.E., by the order of the Pagan emperor Constantine, who declared a few years before, the law of the religious indulgence in the empire -The Nicene Council - was formed.
Constantinerealized that the conflict between Christian churches was affecting the people in the empire, and threatening the existence of the country. Thus, he decided to set up a general council gathering all Christian parties. He personally set up the council, and 2048 priests from different churches were present. The negotiations lasted for three months without agreeing on one opinion.
The emperor conciliated the conflicting parties, and they presented the Nicene Creed, which made the belief in Jesus’ (PBUH) divinity an official belief for Christians and then for the Roman Empire.
The Nicene Council did not discuss the Holy Spirit or his divinity. The negotiations about him continued between churches until they settled the matter at the First Council of Constantinople.