BASILIO I, emperor of CONSTANTINOPLE, known as the MACEDONIAN. — Born at Adrianople around 827 to a humble family, he seized power through a double assassination: that of the caesar Barda (21 Apr. 866) and that of the emperor himself, Michele III (24 Sept. 867). In ecclesiastical history, he is remembered for his intervention in the affair of Fozio, patriarch of Constantinople. As soon as he came to power (867), B. had Fozio, a friend of Barda, confined in a monastery, and recalled the patriarch s. Ignazio, who had been unjustly deposed. When the latter died (23 Oct. 877), Fozio, who in the meantime had been reconciled with the emperor, again occupied the patriarchal throne. But B. showed regard for the supreme authority of the Church of Rome, which pronounced on the affairs of the patriarchate of Constantinople at the Councils held in Byzantium in 869 and 879, under the presidency of the Roman legates. The intervention of B., who, according to his son Leone VI, saw in the struggle between Fozio and s. Ignazio nothing more than a clerical disagreement “which set certain bishops and priests against other priests and bishops,” was inspired by a keen desire for religious peace in the empire.
B. was also notably active in juridical and legislative matters; of these, the ecclesiastical sphere is particularly concerned with the official manual published in 879 under the title Prochiron, and then, between 879 and 886, in a revised and expanded new edition under the title Epanagoge. He died in 886.