[Gorthaur the Cruel]

I believe, although I don't have the texts to hand, that the three rings were made, and presumably used and worn, before the Alliance. The making of the Three seemed to coincide with the unmasking of Sauron by Celebrimbor at Eregion.

I've always wondered the same thing. It was hundreds of years before the One could be completed & the Three have already been completed. Who bore the Three before Gil-Galad & Galadriel? Or perhaps Celebrimbor hoarded it.