Nicea is commemorated every year right after Pascha. But it is too important to be commemorated only then. In a sense we commemorate Nicea every time we say the Creed—i.e. at least every Sunday. For the Creed is not simply one item in the Liturgy, one piece of furniture within the ecclesiastical house. It constitutes the very walls of that house.
The modern system of international relation, functioning from 1648 to 1945, has its historical roots in the Thirty Years War (1618−1648).