780
year

Year 780 (DCCLXXX) was a leap year starting on Saturday of the Julian calendar, the 780th year of the Common Era (CE) and Anno Domini (AD) designations, the 780th year of the 1st millennium, the 80th year of the 8th century, and the 1st year of the 780s decade. The denomination 780 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Events
By place
Byzantine Empire
September 8 - Emperor Leo IV ("the Khazar") dies after a 5-year reign, in which he has been dominated by his wife Irene of Athens, an iconodule. He is succeeded by his 9-year-old son Constantine VI; due to his minority, Irene and her chief minister Staurakios exercise a regency over him.
Europe
Saxon Wars: King Charlemagne decrees the death penalty for any subdued Saxon refusing Christian baptism. Meanwhile Widukind builds up rebel strength in northern Saxony.
The city of Osnabrück, developed as a marketplace, is founded by Charlemagne (approximate date).
Britain
The city of Aldwych rises as an important trading centre in London, under Mercian control. King Offa of Mercia possibly establishes a royal palace at Aldermanbury, on the site of the old Roman Cripplegate fort and amphitheatre (approximate date).
Asia
King Hyegong of Silla is killed in a revolt, terminating the kingly line of succession of former ruler Muyeol, the architect of Silla's unification of the Korean Peninsula (see 668).
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This entry incorporates text from “780” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.