TiberiusIn 69 Tiberius was at work preparing the accession of Vespasian, who needed Egyptian support in order to be proclaimed emperor. Our prefect knew this and, on July 1, 69, he had his troops and the people of Alexandria swear allegiance to Vespasian. A mere scrap of papyrus bears witness to the festivities Tiberius organized in honor of Vespasian, whom he greeted personally (Papyrus Fouad 8; CPJUD. II 418a). The acclamation in Alexandria was to become the official date of Vespasian’s advent (dies imperii). The new emperor was greatly indebted to the “cold intelligence of the prefect, who revealed his plans neither to his staff nor to his armies,” to quote the incisive words of Claire Préaux.

Source: Joseph Mélèze Modrzejewski. The Jews of Egypt. (p. 187)