It is perfectly plain from the following passage in the Athanasian Creed that a Trinity of Divine persons from eternity is a Trinity of Gods:

There is one person of the Father, another of the Son, and another of the Holy Spirit. The Father is God and Lord, the Son is God and Lord, and the Holy Spirit is God and Lord; yet there are not three Gods and Lords, but one God and Lord, because just as we are forced by Christian verity to confess each person singly to be God and Lord, so we are forbidden by the catholic religion to speak of three Gods or three Lords.

This creed has been accepted by the whole Christian church as worldwide and universal, and it is the source of all current knowledge and acknowledgment of God. Anyone who reads it merely with his eyes open can see that the members of the Council of Nicaea, which gave birth as it were posthumously to the so-called Athanasian Creed, understood the Trinity as a Trinity of Gods. It follows that not only did they understand the Trinity as a Trinity of Gods, but that no other idea of the Trinity is current in the Christian world, because this creed is the source from which all gain their knowledge of God, and everyone subscribes to the belief indicated by its wording.

[2] If anyone doubts that the current belief of the Christian world is in a Trinity of Gods, let me appeal to any witness, lay as well as clerical, to the masters and doctors of universities as well as consecrated bishops and archbishops, and to cardinals in their purple, indeed to the Roman Pontiff himself. Let each consider the matter and then pronounce as the ideas in his mind dictate. Is it not as clear and transparent as water in a crystal goblet, if we follow the words of this universally accepted doctrine about God? For instance, it states that there are three persons, and each of these is God and Lord; and that in accordance with Christian verity they ought to confess or acknowledge each person singly as God and Lord, but the catholic or Christian religion or faith prohibits speaking of or naming three Gods and Lords. So verity and religion, or verity and faith, are not one, but two mutually opposed things. The additional clause, that there are not three Gods and Lords, but one God and Lord, has been inserted to prevent its authors being exposed to ridicule before the whole world, for anyone would laugh at the idea of three Gods. Can anyone fail to see the contradiction in this addition?

[3] If, however, they had said that the Father had a Divine essence, the Son had a Divine essence and the Holy Spirit had a Divine essence, but there were not three Divine essences, but a single and indivisible one, then this mystery might have been capable of explanation, to be precise, by understanding the Father as the originating Divine, the Son as the Divine Human from that origin, and the Holy Spirit as the Divine which proceeds from them, since these three belong to a single God. Or again, if we understand by the Father's Divine something resembling the soul in man, by the Divine Human something resembling the body belonging to that soul, and by the Holy Spirit something resembling the activity which comes from both, then the three essences become intelligible as belonging to one and the same person, and so making up a single, indivisible essence.