A famine in the delta left villages ruined and people starving; Phan Bá Vành used it to gather followers for the longest peasant rising of the early Nguyễn.
Natural disaster
Famine of 1821 in the North
- 1821
- Southeast Asia
Meanwhile, elsewhere
- 1789 – 1799French RevolutionEurope
- 17th century – 19th centuryAge of EnlightenmentEurope
- 1845 – 1852Great Irish FamineEurope
- 1846 – 1848Mexican-American WarMesoamerica and the Caribbean
- 1815 – 1871Unification of ItalyEurope
- 24 June 1812French invasion of RussiaEurope
- 1839 – 1842First Opium WarEast Asia
- 30 April 1803Louisiana PurchaseNorth America