Editing 1812 (section)

=== April–June ===
* [[April 4]] – U.S. President [[James Madison]] enacts a 90-day [[embargo]] on trade with the United Kingdom.
* [[April 8]] – The capital of Finland is moved from [[Turku]] to [[Helsinki]], when Russia's Tsar Alexander I signs an edict moving the Government Council of the [[Grand Duchy of Finland]].<ref>{{Cite web |url=http://www.helsinki200.fi/en/helsinki-1812-2012/1812-emperor-alexander-i-promotes-helsinki-capital-grand-duchy/ |title=Helsinki 200: 8 April 1812 Emperor Alexander I promotes Helsinki to the capital of the Grand Duchy. |access-date=August 1, 2017 |archive-date=August 10, 2017 |archive-url=https://web.archive.org/web/20170810032003/http://www.helsinki200.fi/en/helsinki-1812-2012/1812-emperor-alexander-i-promotes-helsinki-capital-grand-duchy/ |url-status=dead }}</ref>
* [[April 30]] – [[Louisiana]] is admitted as the 18th [[U.S. state]].
* [[May 11]] – [[John Bellingham]] [[Assassination of Spencer Perceval|assassinates]] British [[Prime Minister]] [[Spencer Perceval]], in the lobby of the [[British House of Commons]].<ref>{{cite book |last= Treherne| first= Philip |title=The Right Honourable Spencer Perceval |url=https://archive.org/stream/righthonourables00trehuoft#page/n7/mode/2up |publisher= T. Fisher Unwin |location = London | year = 1909 |pages=193–194 |oclc = 5825009 |url-status = live |archive-url =https://web.archive.org/web/20160408120735/https://archive.org/stream/righthonourables00trehuoft |archive-date = 2016-04-08 }}</ref>
* [[May 16]] – Russian field marshal [[Mikhail Kutuzov]] signs the [[Treaty of Bucharest (1812)|Treaty of Bucharest]], ending the [[Russo-Turkish War (1806–12)]] and annexing [[Bessarabia]] to [[Imperial Russia]].
* [[May 25]] – [[1812 Felling mine disaster|Felling mine disaster]]: A mine explosion at the [[Felling, Tyne and Wear|Felling]] [[colliery]] near [[Jarrow]], England, leaves 96 dead.
* [[June 1]] – [[War of 1812]]: U.S. President [[James Madison]] asks the [[Congress of the United States|U.S. Congress]] to declare war on the United Kingdom.
* [[June 4]] – Following [[Louisiana]]'s admittance as a [[U.S. state]], the territory by that name is renamed the [[Missouri Territory]].
* [[June 16]] – New York State charters the City Bank of New York (later [[Citibank]]).
* [[June 18]] – The [[War of 1812]] between the United States, Canada and the United Kingdom begins with [[United States declaration of war upon the United Kingdom|US declaration]].
* [[June 22]] – France [[1812 French declaration of war on Russia|declared war on Russia]].
* [[June 24]] – [[Napoleon]]'s [[Grande Armée]] crosses the [[Neman River]], and [[French invasion of Russia|invades Russia]].<ref>{{cite book |last=Lieven |first=D. C. B. |date=2010 |title=Russia against Napoleon |url=https://archive.org/details/russiaagainstnap00liev_0 |access-date=15 April 2021 |publisher=Viking |page=134 |isbn=9780670021574}}</ref>