Under Basiliscus
Basiliscus, brother of the empress dowager Verina, the widow of Leo, had expelled Zeno from Constantinople in 475 and sent an army in pursuit of him under Illus and his brother Trocundus into Isauria, where Zeno had taken refuge. The brothers defeated the fugitive emperor (July 476) and blockaded him on a hill ironically named by the locals "Constantinople". Illus also captured Zeno's brother, Longinus, as a tool to keep Zeno under control.
During the blockade, Illus and Trocondus were enjoined by the senate of Constantinople to support Zeno against Basiliscus, with whom they had fallen into odium and contempt; Illus himself was discontent with the usurper, as he had allowed the killing of the Isaurians who remained in the capital after Zeno's flight. So Illus and Trocundus were prevailed on by the promises and gifts of Zeno to embrace his side, and to march with united forces towards the capital. At Nicaea in Bithynia they were met by the troops of Basiliscus under his nephew and general Armatus; but he too was overcome and Basiliscus, forsaken by his supporters, was dethroned and put to death (477).
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