The Nicene Council was created and met in AD 325. While there are many myths as to what they were up to and what they actually did, it was not to change any of the known original documents.

There had been a few issues arise, some had tried to add to the formerly accepted texts of God's Word, one person being Arius.

The Council in essence developed a Creed, made clear the texts that were accepted as the God-breathed texts (canon), and decided on the day to celebrate the resurrection of Christ. I think there were some 318 of them, 2 of which did not show and thus didn't vote (but were on the outs with the council anyway?) the rest were all in one accord... and the vote was 316 to "2" voting FOR the Creed, and Canonization of the manuscripts. (Few groups can get that kind of vote on deciding what to serve at a meal!)

It is well documented in history. I think it makes for good reading (about the Council of Nicea.)