These emperors were Valerian, taken prisoner by Sapor and treated with great indignity by the Persians, a.d. 260; and his son Gallienus, under whom a number of generals, nicknamed the “Thirty Tyrants,” claimed and exercised independent authority. “Gallienus made but feeble and desultory attempts to put any of them down, turning into wretched jests each new humiliation, and taking refuge in sensuality from the hopeless task of state reorganization.”—Dict. Chr. Biog. s. voc.