After the Battle of Manzikert (1071) in eastern Asia Minor, Byzantium lost most of Anatolia to the Turks and ceased to be a world power. Partly solicited by the Byzantines, the Crusades proved another disaster: they brought the establishment of Latin principalities on former imperial territories and the replacement of Eastern bishops by a Latin hierarchy. The culminating point was, of course, the sack of Constantinople itself in 1204, the enthronement of a Latin emperor on the Bosporus, and the installation of a Latin patriarch in Hagia Sophia. Meanwhile, the Balkan countries of Bulgaria and Serbia secured national emancipation with Western help, the Mongols sacked Kiev (1240), and Russia became a part of the Mongol empire of Genghis Khan. The Byzantine heritage survived this series of tragedies mainly because the Orthodox church showed an astonishing internal strength and a remarkable administrative flexibility.
Peter the Hermit leading the First Crusade, Abreviamen de las estorias, 14th century.The British Library (Public Domain)
Until the Crusades, and in spite of such incidents as the exchanges of anathemas between Michael Cerularius and the papal legates in 1054, Byzantine Christians did not consider the break with the West as a final schism. The prevailing opinion was that the break of communion with the West was due to a temporary takeover of the venerable Roman see by misinformed and uneducated German “barbarians” and that eventually the former unity of the Christian world under the one legitimate emperor—that of Constantinople—and the five patriarchates would be restored. This utopian scheme came to an end when the Crusaders replaced the Greek patriarchs of Antioch and Jerusalem with Latin prelates, after they had captured these ancient cities (1098–99). Instead of reestablishing Christian unity in the common struggle against Islam, the Crusades demonstrated how far apart Latins and Greeks really were from each other. When finally, in 1204, after a shameless sacking of the city, the Venetian Thomas Morosini was installed as patriarch of Constantinople and confirmed as such by Pope Innocent III, the Greeks realized the full seriousness of papal claims over the universal church: theological polemics and national hatreds were combined to tear the two churches further apart.
After the capture of Constantinople, the Orthodox patriarch John Camaterus fled to Bulgaria and died there in 1206. A successor, Michael Autorianus, was elected in Nicaea (1208), where he enjoyed the support of a restored Greek empire. Although he lived in exile, Michael Autorianus was recognized as the legitimate patriarch by the entire Orthodox world. He continued to administer the immense Russian metropolitanate. The Bulgarian church received from him—and not his Latin competitor—its right for ecclesiastical independence with a restored patriarchate in Trnovo (1235). It was also with the Byzantine government at Nicaea that the Orthodox Serbs negotiated the establishment of their own national church; their spiritual leader, St. Sava, was installed as autocephalous archbishop of Serbia in 1219. The Mongol invasion
The invasion of Russia by the Mongols had disastrous effects on the future of Russian civilization, but the church survived, both as the only unified social organization and as the main bearer of the Byzantine heritage. The “metropolitan of Kiev and all Russia,” who was appointed from Nicaea or from Constantinople, was a major political power, respected by the Mongol Khans. Exempt from taxes paid by the local princes to the Mongols and reporting only to his superior (the ecumenical patriarch), the head of the Russian church acquired an unprecedented moral prestige—though he had to abandon his cathedral see of Kiev, which had been devastated by the Mongols. He retained ecclesiastical control over immense territories from the Carpathian Mountains to the Volga River, over the newly created episcopal see of Sarai (near the Caspian Sea), which was the capital of the Mongols, as well as over the Western principalities of the former Kievan empire—even after they succeeded in winning independence (e.g., Galicia) or fell under the political control of Lithuania and Poland. Attempts at ecclesiastical union and theological renaissance
In 1261 the Nicaean emperor Michael Palaeologus recaptured Constantinople from the Latins, and an Orthodox patriarch again occupied the see in Hagia Sophia. From 1261 to 1453 the Palaeologan dynasty presided over an empire that was embattled from every side, torn apart by civil wars, and gradually shrinking to the very limits of the imperial city itself. The church, meanwhile, kept much of its former prestige, exercising jurisdiction over a much greater territory, which included Russia as well as the distant Caucasus, parts of the Balkans, and the vast regions occupied by the Turks. Several patriarchs of this late period—e.g., Arsenius Autorianus (patriarch 1255–59, 1261–65), Athanasius I (patriarch 1289–93, 1303–10), John Calecas (patriarch 1334–47), and Philotheus Coccinus (patriarch 1353–54, 1364–76)—showed great independence from the imperial power, though remaining faithful to the ideal of the Byzantine oikoumenē.
Without the military backing of a strong empire, the patriarchate of Constantinople was, of course, unable to assert its jurisdiction over the churches of Bulgaria and Serbia, which had gained independence during the days of the Latin occupation. In 1346 the Serbian church even proclaimed itself a patriarchate; a short-lived protest by Constantinople ended with recognition in 1375. In Russia, Byzantine ecclesiastical diplomacy was involved in a violent civil strife. A fierce competition arose between the grand princes of Moscow and Lithuania, who both aspired to become leaders of a Russian state liberated from the Mongol yoke. The “metropolitan of Kiev and all Russia” was by now residing in Moscow and, as in the case of the metropolitan Alexis" class="md-crosslink">St. Alexis (1354–78), often played a directing role in the Muscovite government. The ecclesiastical support of Moscow by the church was decisive in the final victory of the Muscovites and had a pronounced impact on later Russian history. The dissatisfied western Russian principalities (which would later constitute Ukraine) could only obtain—with the strong support of their Polish and Lithuanian overlords—the temporary appointment of separate metropolitans in Galicia and Belorussia. Eventually, late in the 14th century, the metropolitan residing in Moscow again centralized ecclesiastical power in Russia. Relations with the Western church
One of the major reasons behind this power struggle in the northern area of the Byzantine world was the problem of relations with the Western church. To most Byzantine churchmen, the young Muscovite principality appeared to be a safer bulwark of Orthodoxy than the Western-oriented princes who had submitted to Roman Catholic Poland and Lithuania. Also, an important political party in Byzantium itself favoured union with the West in the hope that a new Western Crusade might be made against the menacing Turks. The problem of ecclesiastical union was in fact the most burning issue during the entire Palaeologan period.
Emperor Michael Palaeologus (1259–82) had to face the aggressive ambition of the Sicilian Norman king Charles of Anjou, who dreamed of restoring the Latin empire in Constantinople. To gain the valuable support of the papacy against Charles, Michael sent a Latin-inspired confession of faith to Pope Gregory X, and his delegates accepted union with Rome at the Council of Lyons (1274). This capitulation before the West, sponsored by the emperor, won little support in the church. During his lifetime, Michael succeeded in imposing an Eastern Catholic patriarch, John Beccus, upon the church of Constantinople, but upon Michael’s death an Orthodox council condemned the union (1285).