Editing 1826 (section)

=== April–June ===
* [[April 1]] – In the U.S., [[Samuel Morey]] patents an [[internal combustion engine]].
* [[April 10]] – The [[Third Siege of Missolonghi]] ends and is followed by the massacre of thousands of Greek defenders by the Ottoman besiegers.
* [[May 5]] – The [[Liverpool and Manchester Railway]], designed by [[George Stephenson]] and [[Joseph Locke]], destined to become the world's first purpose-built [[railway]] operated by [[steam locomotive]]s by 1830, is opened after receiving authorisation by the [[Parliament of the United Kingdom]].<ref>{{cite book|author =Carlson, Robert E.|title=The Liverpool & Manchester Railway Project 1821–1831|publisher=David & Charles|location=Newton Abbot|year=1969|isbn=0-7153-4646-6}}</ref>
* [[May 28]] – The Emperor [[Pedro I of Brazil]] abdicates as King of Portugal.
* [[June 14]]–[[June 15|15]] – The [[Auspicious Incident]]: [[Mahmud II]], [[sultan]] of the [[Ottoman Empire]], crushes the last mutiny of [[janissaries]] in [[Istanbul]].
* [[June 20]] – The [[Burney Treaty]] is signed in Bangkok between the [[United Kingdom]] and the [[Rattanakosin Kingdom (1782–1932)|Rattanakosin Kingdom]] of Siam, securing British power in [[southeast Asia]].<ref name=CBH>{{cite book|last=Palmer|first=Alan|last2=Palmer |first2=Veronica|year=1992|title=The Chronology of British History|publisher=Century Ltd|location=London|isbn=0-7126-5616-2}}</ref>
* [[June 21]] – [[Greek War of Independence]]: The attempted [[Ottoman–Egyptian invasion of Mani]] begins.
* [[June 22]] – The [[Pan-Americanism|Pan-American]] [[Congress of Panama]] is opened in [[Panama City]] by [[Simon Bolivar]] as an attempt to unify the republics of the Americas that had recently declared independence from Spain, or to at least make a federation to agree on a common defense policy and create a common military. The Congress lasts for 23 days without an agreement.<ref name=Reinhold>Frances L. Reinhold, "New research on the first pan-American congress held at Panama in 1826." ''Hispanic American Historical Review'' 18.3 (1938): 342-363 [https://read.dukeupress.edu/hahr/article-pdf/18/3/342/754002/0180342.pdf online]. </ref>