Proterius, St., patriarch of Alexandria, was presbyter and church-steward

under Dioscorus, and left in charge of the church when Dioscorus went to the

council of Chalcedon. After Dioscorus was deposed by that council, the emperor

Marcian ordered a new election to the see. The suffragan bishops, except 13

detained at Constantinople by a resolution of the council (Chalced. c. 30), were assembled in synod; and the chief laymen of Alexandria came as usual to express their mind and assent to the prelate's choice (cf. Liberat. Breviar. c. 14, and Evagr. ii. 5). There was great difficulty in reaching a conclusion; for the majority of the Alexandrian church people were profoundly aggrieved by the action of the council. In their eyes Dioscorus was still their rightful "pope," the representative of Cyril and of Athanasius. Ultimately, however, opposition to the imperial mandate was felt impracticable. It was resolved to elect, and then all favoured Proterius, who was consecrated and enthroned ( 452); but the passions of the Dioscorian and anti-Dioscorian parties broke .out at once into tumultuous dissension, which Evagrius likens to the surging of the sea. Proterius sending Leo the usual announcement of his elevation, Leo asked some definite assurance of his orthodoxy (Leo, Ep. 113, in Mar. 453), and received a letter which he regarded as "fully satisfactory," shewing Proterius to be a "sincere assertor of the Catholic dogma," inasmuch as he had cordially accepted the Tome (Epp. 127, 130). Thereupon (Mar. 454) he wrote again to Proterius, advising him to clear himself from all suspicion of Nestorianizing, by reading to his people certain passages from approved Fathers, and then shewing that the Tome did but hand on their tradition and guard the truth from perversions on either side. Leo took care, in thus addressing the "successor of St. Mark," to dwell on that evangelist's relation to St. Peter as of a disciple to a teacher; and he bespeaks the support of the Alexandrian see in this resistance to the unprincipled ambition of Constantinople, which in the 28th canon, so called, of Chalcedon had injured the "dignity" of the other great bishoprics (Ep. 129). Another question prolonged the correspondence. The Nicene Fathers were believed to have commissioned the Alexandrian bishops to ascertain and signify the right time for each coming Easter. Leo had consulted Cyril as to the Easter of 444; and he now, in 454 applied to Proterius, through the emperor, for his opinion as to the Easter of 455, which the Alexandrian Paschal table appeared to him to place too late (Epp. 121, 127). Proterius replied to Leo at some length (Ep. 133, Apr. 454) that Egypt and the East would keep Apr. 24 as Easter Day, and expressed his belief that all Christians everywhere would "observe one faith, one baptism, and one most sacred paschal solemnity."