The new enemies in the West were the Normans, who began their conquest of South Italy early in the 11th century. Basil II’s project of recovering Sicily from the Arabs had been almost realized in 1042 by the one great general of the post-Macedonian era, George Maniaces, who was recalled by Constantine IX and killed as a pretender to the throne. The Normans thereafter made steady progress in Italy. Led by Robert Guiscard, they carried all before them; in April 1071, Bari, the last remaining Byzantine stronghold, fell after a three-year siege. Byzantine rule in Italy and the hope of a reconquest of Sicily were at an end.
The disasters at Manzikert and at Bari, in the same year 1071, at opposite extremes of the empire, graphically illustrate the decline of Byzantine power. The final loss of Italy seemed to underline the fact of the permanent division between the Greek East and the Latin West, which was now not only geographical and political but also increasingly cultural and ecclesiastical. In 1054 a state of schism had been declared between the churches of Rome and Constantinople. The political context of the event was the Norman invasion of Italy, which at the time was a matter of as much concern to the papacy as it was to Byzantium. But the event itself, the excommunication of the patriarch Michael Cerularius by Cardinal Humbert in Constantinople, symbolized an irreconcilable difference in ideology. The reform movement in the Roman Church had emphasized an ideal of the universal role of the papacy that was wholly incompatible with Byzantine tradition. Both sides also deliberately aggravated their differences by reviving all the disputed points of theology and ritual that had become battle cries during the Photian Schism in the 9th century. The schism of 1054 passed unnoticed by contemporary Byzantine historians; its significance as a turning point in East-West relations was fully realized only later.
Schism of 1054Map of the Schism of 1054.Encyclopædia Britannica, Inc./Kenny Chmielewski Alexius I and the First Crusade
But even the events of 1071 had not made the decline of Byzantium irretrievable. The shrinking of its boundaries reduced the empire from its status as a dominating world power to that of a small Greek state fighting for survival. That survival now depended on the new political, commercial, and ecclesiastical forces in the West, for it could no longer draw on its former military and economic resources in Anatolia. The civil aristocracy of Constantinople yielded with bad grace. After four years of civil war, the military lords triumphed with the accession of Alexius I Comnenus, the greatest soldier and statesman to hold the throne since Basil II. The history of his reign was written in elegant Greek by his daughter Anna Comnena; and, as she remarks, it began with an empire beset by enemies on all sides. The Normans captured Dyrrhachium (modern Durrës, Albania) in 1082 and planned to advance overland to Thessalonica. Alexius called on the Venetians to help him, but Robert Guiscard’s death in 1085 temporarily eased the Norman problem. The following year the Seljuq sultan died, and the sultanate was split by internal rivalries. Fortune thus played into Alexius’s hands by ridding him of two of his besetting enemies. By his own efforts, however, he defeated the Pechenegs in 1091.
Alexius I Comnenus, detail of an illumination from a Greek manuscript; in the Vatican Library.Biblioteca Apostolica Vaticana
The Venetians had been pleased to help drive the Normans out of the Adriatic Sea but demanded a heavy price. In 1082 Alexius granted them trading privileges in Constantinople and elsewhere on terms calculated to outbid Byzantine merchants. This charter was the cornerstone of the commercial empire of Venice in the eastern Mediterranean. But it fed the flames of Byzantine resentment against the Latins, and it provoked the rich, who might have been encouraged to invest their capital in shipbuilding and trade, to rely on the more familiar security of landed property.
The terms that Alexius made with his enemies in the first 10 years of his reign were not meant to be permanent. He fully expected to win back Anatolia from the Seljuqs; his plans, however, were not given time to mature, for matters were precipitated by the arrival in the East of the first Crusaders from western Europe (1096). Alexius had undoubtedly solicited the help of mercenary troops from the West but not for the liberation of the Holy Land from the infidels. The urgent need was the protection of Constantinople and the recovery of Anatolia. The Byzantines were more realistic about their Muslim neighbours than the distant popes and princes of the West. Jerusalem had finally been taken by the Seljuqs in 1071, but the most immediate threat to Byzantium came from the Pechenegs and the Normans. Alexius was tactful in his dealings with the pope and ready to discuss the differences between the churches. But neither party foresaw the consequences of Pope Urban II’s appeal in 1095 for recruits to fight a Holy War. The response in western Europe was overwhelming. The motives of those who took the cross as Crusaders ranged from religious enthusiasm to a mere spirit of adventure or a hope of gain, and it was no comfort to Alexius to learn that four of the eight leaders of the First Crusade were Normans—among them Bohemond, the son of Robert Guiscard. Since the Crusade had to pass through Constantinople, however, the Emperor had some control over it. He required its leaders to swear to restore to the empire any towns or territories they might conquer from the Turks on their way to the Holy Land. In return he gave them guides and a military escort. Still, the cost was enormous, for the Crusaders had to be supplied with food or live off the land as they went.
Nicaea fell to them in 1097 and was duly handed over to the Emperor in accord with the agreement. In 1098 they reached and captured Antioch. There the trouble started. Bohemond refused to turn over the city and instead set up his own principality of Antioch. His example was imitated in the establishment of the Latin kingdom of Jerusalem (1100), which had fallen to the Crusaders the year before, and of the counties of Edessa and Tripoli. The Crusaders settled down to colonize and defend the coast of Palestine and Syria and to quarrel among themselves. While they did so, Alexius was able to establish a new and more secure boundary between Byzantium and Islām through the middle of Anatolia. Full advantage was taken of the prevailing rivalry between the Seljuq sultans at Konya and the rival dynasty of the Dānishmend emirs at Melitene (near modern Malatya, Turkey), and a limit was set to the westward expansion of the Turks.
The First Crusade thus brought some benefits to Byzantium. But nothing could reconcile the emperor to Bohemond of Antioch. In 1107 Bohemond mounted a new invasion of the empire from Italy. Alexius was ready and defeated him at Dyrrhachium in 1108. Byzantine prestige was higher than it had been for many years, but the empire could barely afford to sustain the cost of being a great power. Alexius reconstituted the army and re-created the fleet, but only by means of stabilizing the gold coinage at one-third of its original value and by imposing a number of supplementary taxes. It became normal practice for taxes to be farmed out, which meant that the collectors recouped their outlay on their own terms. People in the provinces had the added burden of providing materials and labour for defense, communications, and provisions for the army, which now included very large numbers of foreigners. The supply of native soldiers had virtually ceased with the disappearance or absorption of their military holdings. Alexius promoted an alternative source of native manpower by extending the system of granting estates in pronoia (by favour of the emperor) and tying the grant to the military obligation. The recipient of a pronoia was entitled to all the revenues of his estate and to the taxes payable by his tenants (paroikoi), on condition of equipping himself as a mounted cavalryman with a varying number of troops. He was in absolute possession of his property until it reverted to the crown upon his death. Similarly, Alexius tried to promote more profitable development of the estates of the church by granting them to the management of laymen as charistikia, or benefices. As an expedient, the pronoia system had advantages both for the state and for the military aristocracy who were its main beneficiaries. But in the long term it hastened the fragmentation of the empire among the landed families and the breakdown of centralized government that the 10th-century emperors had laboured to avert. Later Comneni