The world in 815 AD — what happened that year

12 events the sources record for this year, grouped by region.

What happened

An assassin of Wang Chengzong killed Chancellor Wu Yuanheng in the Jing'an Ward of Chang'an and wounded the Censor Pei Du. (Old Book of Tang (Jiu Tangshu), Annals 舊唐書卷15 元和10年 6月)
Li Shidao hid assassins among the monk Yuan Jing of Songshan and the Jinzhu Yuan of Luoyang, intending to burn the palace, but the garrison commander of Luoyang surrounded and stopped them. (Old Book of Tang (Jiu Tangshu), Annals 舊唐書卷15 元和10年)
Zi Jiazhen, a subordinate of Li Shidao, rebelled at the Eastern Capital; the administrator Lü Yuanying defeated him. (New Book of Tang (Xin Tangshu), Annals 新唐書卷007 德宗·順宗·憲宗元和10年8月)
The Balhae envoy Wang Xiaolian and others met a great wind at sea and turned back, but their ship was broken and could no longer be used. (Nihon Kōki (Later Chronicles of Japan) 日本後紀卷24)
An edict strips Wu Yuanji of his titles and orders the troops of sixteen circuits to attack. (Zizhi Tongjian (Comprehensive Mirror) 資治通鑑卷239)
Li Guangyan defeats the Huaixi army at Linying. (Zizhi Tongjian (Comprehensive Mirror) 資治通鑑卷239)

The emperor summoned officials of fifth rank and above and the Balhae envoys to a banquet, with female musicians performing. (Nihon Kōki (Later Chronicles of Japan) 日本後紀卷24)

Abu al-Saraya is defeated at Ahwaz, captured and executed (Al-Tabari, History of the Prophets and Kings Series III tom.2 (Arg.) [india.history.resource.86977], Annus 200)
Hartama enters Kufa (Al-Tabari, History of the Prophets and Kings Series III tom.2 (Arg.) [india.history.resource.86977], Annus 200)

The Romans plunder and set fire to the new farms that the sick Pope Leo had founded, and try to march on Rome; King Bernard sends Duke Winigis of Spoleto to put down the revolt (Royal Frankish Annals ARF a.815, Kurze 1895 p.143)

On the order of Emperor Ludovicus, Saxon and Abodrite troops cross the Eider River to help King Heriold, who had been driven out, marching into Nordic land at Sinlendi and camping on the coast on the seventh day. Godofrid's sons are on an island with a fleet of 200 ships, so they do not fight; they devastate the neighborhood, take 40 hostages, and return to Saxony (Royal Frankish Annals ARF a.815, Kurze 1895 p.142)
At the Paderborn general assembly the emperor receives Slav chiefs and envoys from the east. Hearing of a plot against Pope Leo's life in Rome, he sends his nephew Bernard, king of Italy, to Rome (Royal Frankish Annals ARF a.815, Kurze 1895 p.142)