A warrant to arrest a Christian, dated 28 February 256, was found among the Oxyrhynchus Papyri ("P. Oxy" 3035). The grounds for the arrest are not given in the document. Valerian's first act as emperor on 22 October 253 was to make his son Gallienus his Caesar and colleague. Early in his reign, affairs in Europe went from bad to worse, and the whole West fell into disorder. In the East, Antioch had fallen into the hands of a Sassanid vassal and Armenia was occupied by Shapur I (Sapor). Valerian and Gallienus split the problems of the empire between them, with the son taking the West, and the father heading East to face the Persian threat.