821 Rebellion of Thomas, a claimant of the throne. He is crowned at Antioch, and lays siege to Constantinople. 822 The Bulgarians, taking advantage of civil discord, invade the empire. Thomas delivered up to Michael, and hanged. 823 The Mohammedans capture Crete. 827 Mohammedan conquest of Sicily begun. It is not completed until 878. 829 =Theophilus= succeeds his father. He is a zealous iconoclast. 831 A Mohammedan invasion of long duration begins. 832 Brilliant victory of Theophilus in Charsiana. The Mohammedans capture Heraclea. 836 Theophilus destroys Zapetra. 838 Mohammedan victory at Dasymon. Amorium is captured. 842 Death of Theophilus, due to chagrin at Mohammedan successes. His son =Michael (III) Porphyrogenitus=, or =the Drunkard=, succeeds at the age of four, with his mother =Theodora= as regent. Image-worship restored at Council of Constantinople. End of the Iconoclastic controversy. Slavonic insurrection in the Peloponnesus suppressed. Failure of an attempt to conquer the Abasges, and to recover Crete. War with the Mohammedans continues. 845 Truce with the Mohammedans. 847 Conversion of the Khazars to Christianity. The Bulgarians follow their example a few years later. 848 Revolt of the Paulicians, who join the Arabs. 854 Theodora retires to private life. 856 Bardas, her brother, becomes cæsar. Photius elected patriarch in place of the deposed Ignatius. 858 A great war with the Arabs begins. Omar lays Pontus waste. Successful campaign of Leo, the commander-in-chief, who is finally captured by the Mohammedans. 860 Michael badly defeated near Melitene. 862 Omar invades Cappadocia, Pontus, and Cilicia. 863 Battle of Amasia. Great victory of Petronas, the emperor’s uncle. Death of Omar. The end of trouble with the Mohammedans for some years. 865 First appearance of the Russians in the empire. They attack Constantinople, but are driven off. 866 Michael kills Bardas with the aid of Basil the Macedonian, who becomes cæsar. 867 Assassination of Michael at the instigation of =Basil=, who takes the throne. Basil removes Photius and restores Ignatius. THE BASILIAN DYNASTY (867-1057 A.D.) 871 The Paulicians attacked and reduced to obedience. 872 Basil takes the field against the Mohammedans. 875-876 Victories of Basil in Cilicia. 877 Death of Ignatius. Photius regains the patriarchate. 881 Basil plans to drive the Mohammedans out of Sicily and Italy. Cyprus recovered and held for eleven years. 885 Nicephorus Phocas expels the Mohammedans from Italy. They still hold Sicily. Accusation against Leo, the emperor’s son, by Santabaren, in which the former narrowly escapes death.