An icon from the time, showing the First Council of Nicea, which opposed Arius' position. Artius is shown at the bottom of the image. The central figure is Constantine.

Arius (born around 260, died 336 in Constantinople) was an early Christian thinker. He lived in Alexandria, but was probably born in Libya. He did not agree with his bishop Alexander who said that Jesus and God were the same. Arius said Jesus and God were not the same since there was a time when Jesus did not exist.