(ὁ Μονομάχος), emperor of the East, A. D. 1042-1054. His surname was given him on account of his personal courage in war. In 1042 the government of the empire was in the hands of two imperial sisters, Zoe, the widow of the emperor Romanus Argyrus, and afterwards of Michael IV. the Paphlagonian, and Theodora, a spinster, who were placed on the throne by the inhabitants of Constantinople, after they had deposed the emperor Michael V. Calaphates, the adopted son of Zoe. The two sisters being afraid of their position, Zoe proposed to Constantine Monomachus that he should marry her; and as she was rather advanced in age, being then upwards of sixty, she allowed the gallant warrior to bring his beautiful mistress, Sclerena, with him to the imperial palace, where the two ladies lived together on the best terms. Constantine was saluted as emperor, and conferred the dignity of Augusta upon Sclerena. Soon after the accession of Constantine, Georgius Maniaces, a brother of Sclerena, who was renowned for his victories over the Arabs, and who then held the command in Italy, raised a rebellion. At the head of a chosen body of troops he crossed the Adriatic, landed in Epeirus, joined an auxiliary army of Bulgarians, and marched upon Constantinople. An assassin delivered the emperor from his fears : Maniaces was murdered by an unknown hand in the midst of his camp.
A still greater danger arose in 1043 from an invasion of the Russians, who appeared with a powerful fleet in the Bosporus, while a land force penetrated as far as Varna : but the fleet was dispersed or taken in a bloody engagement, and the Russian army was routed by Catacalo.
In 1047, while absent on an expedition against the Arabs, Constantine received news of another rebellion having broken out, headed by Tornicius, a relative of the emperor, who assumed the imperial title, and laid siege to Constantinople. The emperor hastened to the defence of his capital, broke the forces of the rebel in a decisive battle, and Tornicius, having fallen into the hands of his pursuers, was blinded and confined to a monastery. Constantine was not less fortunate in a war with Cacicus, the vassal king of Armenia and Iberia, who tried to make himself independent; but, unable to take the field against the imperial armies, he was at last compelled to throw himself at the feet of the emperor and implore his clemency. His crown was taken from him, but he was allowed to enjoy both life and liberty, and spent the rest of his days in Cappadocia, where his generous victor had given him extensive estates. Iberia and Armenia were reunited under the immediate authority of the Greeks.
While the frontiers of the empire were thus extended in the East, Thrace and Macedonia suffered dreadfully from an invasion of the Petchenegues, who were so superior to the Greeks in martial qualities, that they would have conquered all those provinces which they had hitherto only plundered, but for the timely interference of the emperor's body-guards, composed of Waregians or Normans, who drove the enemy back beyond the Danube, and compelled them to beg for peace. (A. D. 1053.) At the same time the Normans made great progress