820s BC
This article concerns the period 829 BC – 820 BC.- 828 BC/827 BC —King Xuan of Zhou becomes King of the Zhou Dynasty of China, ending almost two decades of the Gonghe Regency.
- 828 BC—Xiong Yan is replaced by his son Xiong Shuang as Viscount of Chu.
- 825 BC—Takelot II, king of Egypt, dies. Crown Prince Osorkon III and Shoshenq III, sons of Takelot, battle for the throne.
- 825 BC/824 BC—Ariphron, King of Athens, dies after a reign of 20 years and is succeeded by his son Thespieus.
- 825 BC—Dido, founder of Carthage flees Tyre after the death of Acerbas
- 823 BC—Death of Shalmaneser III, king of Assyria. He is succeeded by his son Shamshi-Adad V.
- 821 BC—Xiong Xun, youngest brother of Xiong Shuang, ascends the throne of Chu after defeating his surviving brothers Xiong Xue and Xiong Kan.
- 820 BC—Pygmalion ascends the throne of Tyre.
