833

Events

Byzantine-Arab War: Emperor Theophilos signs an armistice for peace with the Abbasid Caliphate. He offers Caliph Al-Ma'mun 100,000 gold dinars, in return for 7,000 Byzantine prisoners.<ref name="Nor">J. Norwich, Byzantine: The Apogee, p. 47.</ref>

June – Lothair I, eldest son of Emperor Louis the Pious, joins the rebellion of his brothers Pepin I and Louis the German, with the assistance of Archbishop Ebbo. Louis is forced to abdicate, on the plains of Rothfield (near Colmar).
Mojmir I, Moravian duke, expels Prince Pribina from his homeland (western part of modern Slovakia). He unifies Great Moravia and becomes the first known ruler of the Moravian Slavs, who founds the House of Mojmir (approximate date).
Galindo Aznárez I, Frankish count, usurps the Catalan counties (pagi) of Pallars and Ribagorza, in the Spanish March (modern Spain), a buffer zone between the Pyrenees and the Ebro River.

Caliph al-Mamun (r. 813–833) of the Abbasid dynasty

August 7 – Caliph Al-Ma'mun dies after a 20-year reign. He is succeeded two days later by his half-brother al-Mu'tasim, as ruler of the Abbasid Caliphate.
Ibn Hisham, Muslim historian, collects oral traditions that form the basis for the biography of the Islamic prophet Muhammad.

Emperor Junna abdicates the throne, after a 10-year reign. He is succeeded by his nephew Nimmyō, as the 54th emperor of Japan.