Battle of Edington
Alfred the Great defeats the Danes and saves Wessex

In May 878 King Alfred of Wessex, who had spent the winter hiding in the Somerset marshes, raised the levies and defeated the Danish leader Guthrum. Guthrum was baptised and England was divided: the east went to the Danes as the Danelaw, the south and west stayed English.
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Meanwhile around the world (±25 years)
Eastern Europe & Russia
- c. 862 Calling of the Varangians — 16 years earlier
- 882 Oleg takes Kiev — 4 years later
Africa
- 859 Fatima al-Fihri founds al-Qarawiyyin — 19 years earlier
- c. 900 The bronzes of Igbo-Ukwu — 22 years later
Asia
- 868 The Diamond Sutra is printed — 10 years earlier
Americas
- c. 900 Rise of Chichen Itza — 22 years later
Alive at the time
- Rurik (aged 48)
- Oleg the Wise (aged 33)
- Alfred the Great (aged 29)
- Al-Farabi (aged 6)
- Igor of Kiev (aged 0)
- Abu al-Hasan al-Ash'ari (aged 5)
- Edward the Elder (aged 4)