History
840
General
Population: 225 Million*
- Religion: Paschasius Radbertus Abbot of Corbey fathers the doctrine of transubstantiation
- Deaths: Frankish diplomat Einhard, Louis I the Pious King/Emperor
Asia
- Burma: End of Pyu city-states in Burma
Europe
- Eastern Europe: Moimir/Mojmir forms confederation of Slavs in Bohemia, Moravia, Slovakia, Hungary and Transylvania
- France: Death of Einhard the Frankish court diplomat and scholar
- Holy Roman Empire: Death of Louis I the Pious (Franks/HRE) – Lothar (son) becomes emperor but brothers allied against him
Prestiege of Holy Roman Empirre reduced
- Ireland: Danish settlers found Dublin and Limerick
Middle East
- Turkey: Kirghiz Turks conquer Ulghur Turks (Uighur)