The Ben. Ed. points out that what is related by Basil, of the kindness of the bishops of Rome to other churches, is confirmed by the evidence both of Dionysius, bishop of Corinth (cf. Eusebius, Hist. Ecc. iv. 23), of Dionysius of Alexandria (Dionysius to Sixtus II. Apud Euseb., Ecc. Hist. vii. 5), and of Eusebius himself who in his history speaks of the practice having been continued down to the persecution in his own day.  The troubles referred to by Basil took place in the time of Gallienus, when the Scythians ravaged Cappadocia and the neighbouring countries.  (cf. Sozomen, ii. 6.)  Dionysius succeeded Sixtus II. at Rome in 259.