In the summer of 357, Ursacius and Valens, the advocates of this latter group of dissidents in the West, through the influence which they were enabled to bring to bear upon the Emperor by means of his second wife, Aurelia Eusebia (Panegyr. Jul. Orat., iii; Ammianus, XXI, vi, 4), succeeded in bringing about a conference of bishops at Sirmium.
Basil persuaded Constantius to summon a general council, Ancyra being proposed, then Nicomedia (both in Asia Minor), but as the latter city was destroyed by an earthquake, Basil was again at Sirmium in 359 where the Arianizers had meanwhile regained their footing; with Germinius of Sirmium, George of Alexandria, Ursacius and Valens, and bishop (later saint) Marcus of Arethusa, he held a conference which lasted until night.