Humbert of Silva Candida

Humbert of Silva Candida, O.S.B., also known as Humbert of Moyenmoutier (c. 1000 to 1015 – 5 May 1061) was a French Benedictine abbot and later cardinal. It was his act of excommunicating the Patriarch of Constantinople, Michael I Cerularius, in 1054 that is generally regarded as the precipitating event of the East–West Schism between the Roman Catholic Church and the Eastern Orthodox Church.