12 events the sources record for this year, grouped by region.
What happened
Japan (1)
Report from Dazaifu: 110 Silla people in five ships came to Kochika-shima (小近嶋) and fought with the local people; nine were killed and 101 captured. Those who came over to be naturalized are to be handled by custom; those who wish to return are to be sent back. (Nihon Kōki (Later Chronicles of Japan) 日本後紀 卷23)
West Asia (8)
In spring the emperor sends Amalharius, bishop of Trier, and Petrus, abbot of Nonantula, to Constantinople to confirm the peace with Emperor Michael (Royal Frankish Annals ARF a.813, Kurze 1895 p.137)
The army of Michael I faces Krum's camp near Adrianople. After frequent skirmishes a great battle breaks out (Skylitzes–Kedrenos, Synopsis of Histories part_09.txt L2981)
During the battle Leo withdraws his unit and flees. The army scatters in flight. Leo is acclaimed emperor by the army (Skylitzes–Kedrenos, Synopsis of Histories part_09.txt L3051)
Death of al-Amin — his boat capsized; he was captured and executed (Al-Tabari, History of the Prophets and Kings Series III tom.2 (Arg.) [india.history.resource.86977], Annus 198)
Leo, the commander of the East, is raised up by the army, acclaimed Roman emperor on the platform before the capital, and about noon enters by the Golden (Chrysê) Gate and goes into the palace. (Theophanes, Chronographia part_10.txt 줄 94~108)
Hearing of Leo's elevation, Michael takes refuge with his wife (the original "Proco-cia" breaks at a line end) and children in a prayer house beside the market, has his head shaved and puts on a monk's habit. (Theophanes, Chronographia part_10.txt 줄 108~110)
On 11 July, at the ambo of the great church, Patriarch Nikephoros places the crown on Leo (coronation). (Theophanes, Chronographia part_10.txt 줄 110~112)
Leo launches a surprise attack on the Bulgarians and wins a great victory. Reportedly many on the side of the Bulgarian king Krum were killed or captured (Skylitzes–Kedrenos, Synopsis of Histories part_09.txt L3318)
Western Europe (1)
King Egbert ravaged Cornwall from east to west. (Anglo-Saxon Chronicle Giles/Ingram 1847 A.D. 813 항 (pg657.txt 줄 2495))