Michael I Keroularios

   Patriarch of Constantinople (qq.v.) from 1043-1058 who was a chief participant in the church schism of 1054 (q.v.). In 1052 Keroularios closed down Latin churches in Constantinople because they used azyma (q.v.), i.e., unleavened bread, in the Eucharist (q.v.). This was in response to the Norman (q.v.) closure of Byzantine churches in southern Italy (q.v.), with papal approval. When Pope Leo IX (qq.v.) complained about Keroularios's use of the title "ecumenical," the stage was set. The pope sent an embassy to Constantinople (q.v.) led by his secretary Humbert (q.v.). Humbert's impetuosity led to mutual excommunications that inaugurated the church schism of 1054 (q.v.). As a result, Constantine IX's (q.v.) pro-papal policy, directed by Argyros (q.v.) against the Normans of southern Italy (qq.v.), lay in shambles. In one sense, it proved to be a personal victory for Keroularios, who was pleased to see imperial support of the papacy destroyed. Moreover, Keroularios now knew about the Donation of Constantine (q.v.), and he redefined patriarchal authority in terms comparable to the authority claimed by the papacy (q.v.). When Constantine IX died the following year (1055), Keroularios's victory seemed complete. The patriarch emerged from these events as the most powerful personality in Constantinople, who attracted enormous popular support.