Editing 1821 (section)

=== July–September ===
[[File:Coronation of George IV.jpg|200px|thumb|right|July 19: Coronation of [[George IV of the United Kingdom]]]]
[[File:La Independencia del Perú.jpg|200px|thumb|right|July 28: Proclamation of the [[Independence of Peru]]]]
[[File:Firma del Acta de Independencia de Centroamérica.jpg|200px|thumb|right|September 15: Declaration of [[Independence of Central America]]]]
[[File:Entrada del Generalisimo Don Agustin de Iturbide a Mexico.jpg|200px|thumb|right|September 27: Entrance of the [[Army of the Three Guarantees]] to Mexico City]]
* [[July 4]] – Return of [[John VI of Portugal|John VI]] from Brazil to Portugal who approves on that day the ''Bases da Constituição''.
* [[July 19]] – [[George IV of the United Kingdom|George IV]] is crowned King of the [[United Kingdom of Great Britain and Ireland]]. His estranged wife, [[Caroline of Brunswick]], is turned away from the ceremony.
* [[July 28]] – Argentine general [[José de San Martín]] [[Independence of Peru|declares the independence]] of [[Peru]] from the [[Spanish Empire]].
* [[August 10]] – [[Missouri]] is admitted as the 24th U.S. state.
* [[August 7]] ([[Julian calendar|O.S.]])/[[August 19]] ([[Gregorian calendar|N.S.]]) – [[Navarino massacre]]: Greek rebels massacre 3,000 inhabitants of the city of Navarino.
* [[August 21]] – [[Jarvis Island]] is discovered in the Pacific by the crew of the ''Eliza Frances''.
* [[August 24]] – The [[Treaty of Córdoba]] is signed in [[Córdoba, Veracruz]], Mexico, ratifying the [[Plan of Iguala]] of February 24 for Mexico's independence from Spain and, although not recognised by the latter, effectively concludes the [[Mexican War of Independence]].
* [[August 30]] – At the [[Congress of Cúcuta]], the [[Republic of Gran Colombia]] (a federation covering much of present-day Venezuela, Colombia, Panama, and Ecuador) is established, with [[Simón Bolívar]] as the founding [[President (government title)|President]], and [[Francisco de Paula Santander]] as vice president.
* [[September 4]] – Chilean general [[José Miguel Carrera]] is executed by an Argentinian military tribunal, in the city of [[Mendoza, Argentina|Mendoza]].
* [[September 15]] – Guatemala, El Salvador, Honduras, Nicaragua and Costa Rica gain [[Independence of Central America|independence from Spain]] by the [[Act of Independence of Central America]]. On October 29, the newly independent [[First Mexican Empire]] proposes that Guatemala should be annexed with it.
* [[September 4]] ([[Julian calendar|O.S.]])/[[September 16]] ([[Gregorian calendar|N.S.]]) – [[Ukase of 1821]]: Russia proclaims territorial sovereignty over Northwestern North America, modern-day Alaska.
* [[September 18]] – [[Amherst College]] is founded in [[Massachusetts]].
* [[September 27]] – The [[Army of the Three Guarantees]] enters [[Mexico City]], and the following day the [[Declaration of Independence of the Mexican Empire]] from Spain is proclaimed, following the [[Mexican War of Independence]].