East and West alike the triumphs of the Turk were unmixed evils, and the strife of East and West assumed a new aspect when a barbarous and unteachable soldier, mighty only in destruction, became the chief agent of Eastern advance. It was no longer the continuance of the struggle between Eastern and Western civilisation that was as old as Marathon. Henceforth it was a strife between the only possible civilisation and the most brutal and hopeless barbarism. Yet the superior military efficiency of the Turk put an irresistible weapon into his hands. Since the days of Leo the Isaurian and Charles Martel, the relations of the Eastern and Western worlds had been almost stationary. A new wave of Eastern aggression now set in, to be followed in its turn by a period of Western retaliation. The Seljukian attacks on Armenia and the Empire brought about the Nemesis of the Crusades and the Latin kingdoms of the East. [Sidenote: Decline of the Eastern Empire.] The period of revolution and confusion that had followed the extinction of the Basilian dynasty made the Empire little able to resist the Turkish assault. It is as wearisome as unprofitable to tell in any detail of the purposeless palace intrigues and provincial revolts, that set up and pulled down Emperors in the dreary years that followed the death of Theodora. The first successor of the last of the Macedonians was of her own designation. [Sidenote: Michael VI., 1057.] Michael VI., surnamed Stratioticus (1057), was an aged and incompetent soldier, who within a year succumbed to a revolt of the Asiatic nobles, who seated on the throne one of the most powerful of their number, Isaac I., Comnenus (1057–1059), but the hopes excited by him were rudely dispelled by a disease that drove him into a monastery to die. [Sidenote: Isaac I., Comnenus, 1057–1059.] Another great Cappadocian magnate, Constantine X., Ducas (1059–1067), was now made Emperor. [Sidenote: Constantine X., Ducas, 1059–1067.] He was a pettifogging financier, who disbanded part of his troops and disheartened the rest by miserable and disastrous economies. In his reign the Seljukian assaults first became formidable. On his death in 1067, his widow Eudocia acted as regent for their son, the boy Emperor Michael VII. (1067–1078). [Sidenote: Michael VII., 1067–1078.] Eudocia chose a second husband and co-regent in Romanus Diogenes (1068–1071), a Cappadocian noble, who had won a high reputation for brilliancy as a soldier, but lacked the prudence and policy necessary to a general. [Sidenote: Romanus IV., Diogenes, 1068–1071.] Romanus at once took the field against the Seljukian hordes, who were now devastating Cappadocia with fiendish cruelty, and had just captured Cæsarea and plundered the shrine of St. Basil. But the heavy Greek cavalry, with their formal drill and slow traditional tactics, were only a poor match for the daring valour and rapid movements of the swift light horse that constituted the chief strength of the Turkish army. At