events
May 20, 325
The First Council of Nicaea is formally opened, starting the first ecumenical council of the Christian Church.
First Council of Nicaea
The First Council of Nicaea was a council of Christian bishops convened in the Bithynian city of Nicaea by the Roman Emperor Constantine I. The Council of Nicaea met from May until the end of July 325.
Ecumenical council
An ecumenical council, also called general council, is a meeting of bishops and other church authorities to consider and rule on questions of Christian doctrine, administration, discipline, and other matters in which those entitled to vote are convoked from the whole world (oikoumene) and which secures the approbation of the whole Church.
May 20
May 20 is the 140th day of the year in the Gregorian calendar; 225 days remain until the end of the year.