ALEXIUS I. (1048–1118), emperor of the East, was the third son of John Comnenus, nephew of Isaac Comnenus, emperor 1057–1059. His father declined the throne on the abdication of Isaac, who was accordingly succeeded by four emperors of other families between that date and 1081. Under one of these emperors, Romanus Diogenes (1067–1071), he served with distinction against the Seljuk Turks. Under Michael Parapinaces (1071–1078) and Nicephorus Botaniates (1078–1081) he was also employed, along with his elder brother Isaac, against rebels in Asia Minor, Thrace and in Epirus (1071). The success of the Comneni roused the jealousy of Botaniates and his ministers, and the Comneni were almost compelled to take up arms in self-defence. Bontaniates was forced to abdicate and retire to a monastery, and Isaac declined the crown in favour of his younger brother Alexius, who then became emperor in the 33rd year of his age. His long reign of nearly 37 years was full of difficulties (see Roman Empire, Later). At the very outset he had to meet the formidable attack of the Normans (Robert Guiscard and his son Bohemund), who took Dyrrhachium and Corfu, and laid siege to Larissa in Thessaly. The Norman danger ended for the time with Robert Guiscard’s death (1085) and the conquests were recovered. He had next to repel the invasions of Patzinaks (Petchenegs) and Kumans in Thrace, with whom the Manichaean sects of the Paulicians and Bogomilians made common cause; and thirdly, he had to cope with the fast-growing power of the Turks in Asia Minor. Above all he had to meet the difficulties caused by the arrival of the warriors of the First Crusade, which had been in a great degree initiated owing to the representations of his own ambassadors, though the help which he wanted from the West was simply mercenary forces and not the immense hosts which arrived to his consternation and embarrassment. The first part, under Peter the Hermit, he got rid of by sending them on to Asia Minor, where they were massacred by the Turks (1096). The second and much more serious host of warriors, led by Godfrey of Bouillon, he conducted also into Asia, promising to supply them with provisions in return for an oath of homage, and by their victories recovered for the Empire a number of important cities and islands—Nicaea, Chios, Rhodes, Smyrna, Ephesus, Philadelphia, Sardis, and in fact most of Asia Minor (1097–1099). This is ascribed as a credit to his policy and diplomacy by his daughter, by the Latin historians of the crusade to his treachery and falseness, but during the last twenty years of his life he lost much of his popularity. They were marked by persecution of the followers of the Paulician and Bogomilian heresies (one of his last acts was to burn Basilius, a Bogomilian leader, with whom he had engaged in a theological controversy), by renewed struggles with the Turks (1110–1117), by anxieties as to the succession, which his wife Irene wished to alter in favour of her daughter Anne’s husband, Nicephorus Bryennius for whose benefit the special title panhypersebastos (i.e. as it were augustissimus si quis alius) was created. This intrigue disturbed even his dying hours. He deserves the credit of having raised the Empire from a condition of anarchy and decay at a time when it was threatened on all sides by new dangers. No emperor devoted himself more laboriously or with a greater sense of duty to the task of ruling.
Authorities.—Zonaras xviii. 27-29; Anna Comnena’s Life; see also Du Cange, Familiae Byzantinae; Friedrich Wilken, Rerum ab Alexio I., Joanne, Manuele et Alexio II. Comnenis Romanorum, Byzantinorum imperatoribus gestarum, libri iv. Commentatio (Heidelberg, 1811); Finlay, History of Greece (vol. iii., Oxford, 1877); Gibbon, Decline and Fall of the Roman Empire, edited with notes, &c., by Prof. J. B. Bury (London, 1898), where further authorities are cited; F. Chalandon, Essai sur le règne d’Alexis I er Comnène (1900). (J. B. B.)