|Covid-19|March 1 – Emperor Louis the Pious is restored as sole ruler of the Frankish Empire. After his re-accession to the throne, his eldest son Lothair I flees to Burgundy.
Danish Vikings raid the trading settlement of Dorestad (present-day Wijk bij Duurstede), located in the south-east of the province of Utrecht (modern Netherlands).
Summer – The Viking ship of Oseberg near Tønsberg (modern Norway) is buried in a mound, during the Viking Age (approximate date).
The first mention is made of the Jona River ('the cold one') in Switzerland (approximate date).
King Óengus II dies after a 14-year reign. He is succeeded by his nephew Drest IX, as ruler of the Picts.
July 20 – Ansegisus, Frankish abbot and advisor of former emperor Charlemagne, dies at Fontenelle Abbey in Normandy (or 833).
Aud the Deep-Minded, Irish queen
Lady Shuiqiu, wife of Qian Kuan (d. 901)
Mo Xuanqing, Chinese scholar
Pi Rixiu, Chinese poet (approximate date)
Robert, Frankish nobleman (d. 866)
Tan Quanbo, Chinese warlord (d. 918)
July 20 or 833 – Ansegisus, Frankish abbot
Adelchis I, duke of Spoleto (Italy)
Cellach mac Brain, king of Leinster (Ireland)
Fridugisus, Anglo-Saxon abbot (approximate date)
Gaucelm, Frankish nobleman
Nasr ibn 'Abdallah, Muslim governor
Odo I, Frankish nobleman
Óengus II, king of the Picts
Robert III, Frankish nobleman (b. 800)
Wang Chengyuan, Chinese general (b. 801)
Wang Tingcou, general of the Tang Dynasty
William, Frankish nobleman
Year 834 (DCCCXXXIV) was a common year starting on Thursday (link will display the full calendar) of the Julian calendar.