Tsar Ivan Asen II (1218–1241), conditions were created for the termination of the union with Rome and for the recognition of the autocephalous status of the Bulgarian Orthodox Church. In 1235 a church council was convened in the town of Lampsakos. Under the presidency of Patriarch Germanus II of Constantinople and with the consent of all Eastern Patriarchs, the council confirmed the Patriarchal dignity of the Bulgarian Orthodox Church and consecrated the Bulgarian archbishop German as Patriarch. Despite the shrinking of the diocese of the Tarnovo Patriarchate at the end of the 13th century, its authority in the Eastern Orthodox world remained high. The Patriarch of Tarnovo confirmed the patriarchal dignity of the Serbian Orthodox Church in 1346, despite protests by the Patriarchate of Constantinople. The Tarnovo Literary School developed under the wing of the Patriarchate in the 14th century, with scholars of the rank of Patriarch Evtimiy, Gregory Tsamblak, and Konstantin of Kostenets. A considerable flowering was noted in the fields of literature, architecture, and painting; the religious and theological literature also flourished. Tarnovo fell under domination by the Ottoman Empire in 1393, whose leaders sent Patriarch Evtimiy into exile, the autocephalous church organization was destroyed again the next year and integrated into the Ecumenical Patriarchate. In 1394, the Holy Synod of the Ecumenical Patriarchate gave the authorisation to the Metropolitan of Moldavia, Jeremiah, "to move with the help of God to the holy Church of Turnovo and to be allowed to perform everything befitting a prelate freely and without restraint." By around 1416, the territory of the Patriarchate of Turnovo was totally subordinated to the Ecumenical Patriarchate. The other Bulgarian religious centrethe Ohrid Archbishopric survived until 1767. Ottoman rule As the Ottomans were Muslim, the period of Ottoman rule was the most difficult in the history of the Bulgarian Orthodox Church, to the same extent as it was the hardest in the history of the Bulgarian people. During and immediately after the Ottoman conquest, their forces razed a significant number of Bulgarian churches and monasteries south of the Danube River, including the Patriarchal Cathedral church of the Holy Ascension in Tarnovo. Some of the surviving structures were converted into mosques. Many of the clergy were killed, while the intelligentsia associated with the Tarnovo Literary School fled north of the Danube. Martyrs to the church were made during the forceful conversion to Islam of many districts and almost all