(Νικηφόρος), emperor of Constantonople, A. D. 802-811, was a native of Seleuceia in Pisidia, and by all sorts of court intrigues rose to the important post of logotheta, or minister of finances,with which he was invested by the empress Irene. The prime minister Aetius, an eunuch, conspired against that excellent princess with a view of putting his brother Leo on the throne. His schemes were seen through by several of the grand functionaries of state, and a counterconspiracy took place, which is decidedly one of the most remarkable recorded in history. The principal leaders on both sides were eunuchs, of whom seven were against Aitius, viz., Nicetas, the commander of the guard, his two brothers, Sisinnius and Leo Clocas, the quaestor Theoctistus, Leo of Sinope, Gregorius, and Petrus, all of whom held the patrician rank. Their object was to raise Nicephorus to the throne, and they succeeded through one of those sudden strokes which are so characteristic of the revolutions of Constantinople. On the 31st of October, 802, Nicephorus was suddenly proclaimed emperor. He began his career by deceiving Irene by false promises; and no sooner had she entrusted her safety to him, than he sent her into exile in the island of Lesbos, where she died soon afterwards of misery and grief. The vices of the new master of the empire soon became so conspicuous that he incurred the hatred of the very parties to whom he was indebted for his elevation; but as he was supported by the clergy, and a crowd of reckless characters, he attacked his former friends openly, and put their leader Nicetas to death. Upon this Bardanes. surnamed the Turk, the bravest man and best general of Greece, rose in revolt, was proclaimed emperor by his adherents, and marched against Nicephorus, who was unable to vanquish him in the field, and took refuge in intrigues. Forsaken by his principal supporters Bardanes promised to submit on condition of enjoying his life and property. Both were granted him by the emperor. As soon, however, as Bardanes was in the power of his faithless rival, he was forced to take the monastic habit, had his property confiscated, was deprived of his eyes, and continued till his death to be a victim of unremitting cruelty and revenge. In 803 Nicephorus sent ambassadors to Charlemagne, and received in his turn an embassy from the latter. A treaty was made between them, by which the frontiers of the two empires were regulated: Charlemagne was confirmed in the possession of Istria, Dalmatia, Liburnia, Slavonia, Croatia, and Bosnia; but the Dalmatian islands and sea-towns were left to Nicephorus. In these transactions Nicephorus showed no small deference to his great rival in the West, while he behaved with impudence towards his equally great rival in the East, the khalif Harun-ar-Rashid, who resented the insult by invading the empire. After a bloody war of several years, during which a great portion of Asia Minor was laid waste, Nicephorus was compelled to accept the disgraceful conditions of a peace, by which he was bound to pay to the khalif an annual tribute of 30,000 pieces of gold, out of which three were considered as being paid by the Greek emperor personally, and three others by his son Stauracius. In 807 Nicephorus set out for Bulgaria, being involved in a war with king Crum, and in the same year the Arabs ravaged Rhodes and Lycia. A dangerous conspiracy obliged him to return to Constantinople, where a few months after his arrival another one broke out of which he nearly became a victim. Through the death of Harun-ar-Rashid, in 809, Nicephorus was relieved from his most formidable enemy, but was nevertheless unable to secure peace to his subjects, king Crum of Bulgaria proving as dangerous as the khalif. In order to carry on th e war against the Bulgarians with effect, Nicephorus established a strong and permanent cordon, or army of observation, along the Danube, and oppressed his people with taxes. The public indignation was roused, and an attempt was made to assassinate him. However, he was destined to die a more honourable death. Having drained the people of their gold and silver he was enabled to raise a very strong army, at the head of which he penetrated very far into Bulgaria (811), and so weakened Crum that the latter sued for peace. Nicephorus, proud of his success, rejected the request; but the barbarian king now rose with all the energy of despair, and, as often happens in such cases, ruined the man who was too sure of ruining him. The Greeks being encamped on a plain surrounded on all sides by steep rocks, intersected by a few narrow ravines, Crum contrived to block up all these defiles but one with enormous quantities of dry wood and other combustible materials, which one night were set on fire, while the Bulgarians from all sides shouted their war cries as if they intended to descend into the plain and take the camp by assault. The terrified Greeks rushed towards the only defile that was still open, but there were received by Crum with his main forces, and a conflict in the night ensued in which the Greek army was nearly destroyed, and Nicephorus lost his life, slain either by the enemy or his own enraged soldiers (25th of July 811). His son Stauracius, although badly wounded, escaped and hastened to Constantinople, where he was proclaimed emperor. (Theophan. p. 402, &c.; Cedren. p. 476, &c.; Zonar. vol. ii. p. 121, &c.; Manass. p. 93; Glyc. .. 285, &c.)