Sergius of Samarkand

Sergius of Samarkand, also known as Mār Sargīs or Mar Sergius, was an ascetic and missionary of the Church of the East in which he is considered a major saint. His name is associated with numerous locations in Central Asia. Not much is known about his life except that he had retreated to the Altai Mountains and,^:297 according to Mari ibn Suleiman's Book of the Tower and a letter written in about 1009 by Abdishō, the Metropolitan of Merv, to Catholicos-Patriarch John V in Baghdad, Mar Sergius is responsible for the conversion of the Keraites.