By place Byzantine Empire •
June 22 –
Battle of Versinikia: The
Bulgars, led by
Krum, ruler (
khan) of the
Bulgarian Empire, defeat Emperor
Michael I near
Edirne (modern
Turkey). The
Byzantine army (26,000 men) is destroyed by a counter-attack of Bulgarian
heavy cavalry, while trapped in the valley. Krum captures the Byzantine
camp and a rich prize, including
gold and
weaponry. •
July 11 – Michael I, under threat by conspiracies, abdicates in favor of his general
Leo the Armenian, and becomes a
monk (under the name Athanasius). His sons are
castrated to prevent them succeeding the
Byzantine throne, and relegated into
monasteries. One of them, Niketas (renamed
Ignatius), eventually becomes a
patriarch of Constantinople. •
July 17 – Krum reaches
Constantinople, and
sets his camp outside the walls. He is given an invitation, and a promise of safe conduct, to meet Leo V. Krum sets out unarmed for the capital with only a small escort, but is
ambushed and manages to escape. After this unsuccessful Byzantine murder attempt, the Bulgars ravage much of
Eastern Thrace. • Autumn –
Siege of Adrianople: Krum captures Adrianople—one of the most important Byzantine fortresses in
Thrace—after being attacked with
siege engines. The
garrison is forced to surrender, due to
starvation. On the orders of Krum, the population of the surrounding area (numbering about 10,000) is transferred to Bulgarian territory, north of the
Danube. •
Ashot I ("the Great") becomes the first
Georgian Bagratid prince of
Iberia, under Byzantine protection.
Europe •
September 11 —
Louis the Pious, king of
Aquitaine (and only surviving legitimate son), is crowned co-emperor of the
Franks, with his father
Charlemagne. • Danish
Viking raiders, led by King
Horik I, attack
Vestfold (modern Norway), due to its insubordination (approximate date). •
Third Council of Tours: Priests are ordered to preach in the
vernacular language (either
Vulgar Latin or German).
Abbasid Caliphate • Autumn –
Siege of Baghdad: Caliph
al-Amin surrenders
Baghdad, after al-Ma'mun's General Tahir accepts his peace terms, but he is captured and executed. His brother
al-Ma'mun becomes undisputed ruler of the
Abbasid Caliphate. to the new Abbasid caliph,
al-Ma'mun in 813. (
Tarikh-i Alfi 1593 CE) • The Baghdad School of
Astronomy is opened by al-Ma'mun. • Caliph
al Ma’mun founds a school in
Baghdad called the
House of Wisdom. In this school scholars translated
Greek philosophy classics into Arabic. == Births ==