Here is a webpage that Roger Pearse put together to counter the many internet myths about what happened at Nicaea:
It assembles every piece of data written about it up to 150 years afterwards. Pearse also writes: "The idea that the canon was discussed at Nicaea is no older than Voltaire, and relies on a misreading of a passage in the Vetus Synodicon (a 9th century work), itself the earliest text to even suggest it. These myths are a nuisance to everyone, friend and foe. You've been
led astray (no doubt in good faith) by it; I don't see how anyone benefits from circulating the wrong raw facts, whatever opinions we hold."
You may also want to take a look at the wikipedia page on the Council:
Compare that with the farcical depiction of the Council in Bushby's book (summarized by Robert Adams):
When Emperor Constantine conquered the East in 324, he sent his Spanish religious advisor, Osius of Cordoba, to Alexandria with letters to several Biscops exhorting them to make peace among their own. But the mission failed and Constantine, probably at the suggestions of Osius, then issued a decree commanding all Presbyters and their subordinates "be mounted on asses, mules and horses belonging to the public and travel to the city of Nicaea" in the Roman province of Bithymia, the country of Asia. The Presbyters were instructed by the Emperor to bring with them the manuscripts from which they orated to the rabble (that's us!) "wrapped and bound in leather". Constantine saw in this developing system of belief the opportunity to make a combined state religion and protect it by law. The first general church council was thus convened and the year was 325.
On 21 June, the day of the Summer Solstice, (and under those cult conditions) a total of 2048 "presbyters, deacons, sub-deacons, acolytes and exorcists" gathered at Nicaea to decide what Christianity really was, what it would be, what writings were to be used and who was to be it's God.
Ancient church evidence established that a new 'god' was to be approved by the Roman Emperor and an earlier attempt (circa 210) to deify either Judas Khrestus or his twin brother Rabbi Jesus (or somebody else) had been 'declined'. Therefore, as late as 325, the Christian religion did not have an official god.
After a long and bitter debate, a vote was finally taken and it was with a majority show of hands that Judas Khrestus and Rabbi Jesus both became God (161 votes for and 157 votes against). The Emperor effectively joined elements of the two individual life stories of the twin brothers into a singular creation. The doctrine of the Celtic / British church of the west was democratically attached to the Presbyters stories of the east.
A deification ceremony was then performed 'Apotheosis'. Thus the deified ones were then called 'saviours' and looked upon as gods. Temples, altars, and images with attributes of divinity were then erected and public holidays proclaimed on their birthdays.