Although the operation may have commenced under Septimius Zabbai, Zabdas' second-in-command, the invasion of Asia Minor did not fully begin until Zabdas' arrival in the spring of 271. The Palmyrenes annexed Galatia and, according to Zosimus, reached Ancyra. Bithynia and the Cyzicus mint remained beyond Zenobia's control, and her attempts to subdue Chalcedon failed. The Asia Minor campaign is poorly documented, but the western part of the region did not become part of the queen's authority; no coins with Zenobia or Vaballathus' portraits were minted in Asia Minor, and no royal Palmyrene inscriptions have been found. By August 271 Zabdas was back in Palmyra, with the Palmyrene empire at its zenith.