King Wigstan of Mercia, grandson of former ruler Wiglaf (see 839), declines his kingship in preference of the religious life. He asks his widowed mother, Princess Ælfflæd, to act as regent. A nobleman of the line of the late king Beornred, named Berhtric, wishes to marry her but he is a relative. Wigstan refuses the match, and is murdered by followers of Berhtric at Wistow. He is buried at Repton Abbey, and later revered as a saint. The Mercian throne is seized by Berhtric's father, Beorhtwulf.
Venice sends a fleet of 60 galleys (each carrying 200 men) to assist the Byzantines in driving the Arabs from Crotone, but the attack fails. Muslim troops conquer the city of Brindisi (approximate date).
In the Chinese capital of Chang'an, the West Market (and East Market) are closed every night one hour and three quarters before dusk (by government order); the curfew signals by the sound of 300 beats to a loud gong. After the official markets have been closed for the night, small night markets in residential areas thrive with plenty of customers, despite government efforts to shut them down. With the decline of the government's authority (by mid 9th century), this edict (like many others) is largely ignored, as urban dwellers keep attending the night markets regardless.
Summer – Viking raiders attack Nantes, located on the River Loire; they kill the town's bishop along with many of the clergy, and murder men, women, and children. They plunder the western parts of Aquitaine, and reach an island north of the mouth of the River Garonne, near what later will be La Rochelle. There the Vikings bring materials from the mainland, and build houses to spend the winter.
King Æthelred II of Northumbria is expelled from his kingdom by Rædwulf, who takes the throne. Rædwulf is later killed in battle against the Vikings, along with many of his noblemen. Æthelred returns and claims his right to rule.