The Zograf Monastery was plundered and burnt down by Crusaders, working under orders from the Byzantine emperor Michael VIII Palaiologos, in 1275, resulting in the death of 26 monks. These included the igumen (abbot) Thomas, as well as the monks Barsanuphius, Cyril, Micah, Simon, Hilarion, James, Job, Cyprian, Sabbas, James, Martinian, Cosmas, Sergius, Paul, Menas, Ioasaph, Ioanicius, Anthony, Euthymius, Dometian, Parthenius, and four laymen. The reason for this attack was the opposition of the Athonite monks to the Union of Lyons, which the Emperor had supported for political reasons. Having hanged the Protos (the elected president of Mount Athos), and having killed many monks in Vatopedi, Iveron and other monasteries, the Latins attacked Zographou. Their martyrdom is commemorated annually on October 10 (October 23 on the Gregorian Calendar) throughout the Eastern Orthodox Church.