874

Events

Salomon, duke of Brittany, is murdered by a faction which includes his son-in-law Pascweten and Gurvand, son-in-law of late ruler Erispoe. After Salomon's death they divide the country, and Pascweten and Gurvand co-rule Brittany.
Svatopluk I, ruler of Great Moravia, concludes a peace treaty at Forchheim. He is able to expand his territories outside the Frankish sphere, and subjugates the Vistulans.
Ingólfr Arnarson arrives from Norway, as the first permanent Viking settler in Iceland. He builds his homestead and founds Reykjavík. The settlement of Iceland begins.
Britain
The Danish Vikings drive King Burgred of Mercia into exile, and sack Tamworth. They conquer his kingdom and install his political opponent, Ceolwulf II, as sub-king.
Autumn – The Great Heathen Army splits into two bands; Halfdan returns with his forces to Northumbria, along with his brother Ubba, where he establishes a new base on the River Tyne.
Amlaíb Conung, the first Norse 'king' of Dublin, is killed in Scotland, during a campaign against his rival Constantin I.
November – Frost begins in Scotland, and lasts until April 875.
China
Huang Chao, a salt privateer, joins forces with Wang Xianzhi to raise a rebel army at Changyuan. The uprising further weakens the Tang dynasty, which is already weakened by natural disasters such as severe droughts and floods.
By topic

March 13 - The remains of Saint Nikephorus I are interred in the Church of the Holy Apostles, in Constantinople.
The monastery of Sevanavank, located on the shore of Lake Sevan, is founded.
Muhammad al-Mahdi, the child of the eleventh Shi'i Twelver Imam Hasan al-Askari, begins his Imamate. His first period of occultation, known as the Minor Occultation, also begins.