Editing April 30 (section)

===1601–1900===
*[[1636]] &ndash; [[Eighty Years' War]]: [[Dutch Republic]] forces recapture a strategically important fort from Spain after [[Siege of Schenkenschans|a nine-month siege]].
*[[1789]] &ndash; On the balcony of [[Federal Hall]] on [[Wall Street]] in New York City, [[George Washington]] takes the [[First inauguration of George Washington|oath of office]] to become the first [[President of the United States]].
*[[1803]] &ndash; [[Louisiana Purchase]]: The United States purchases the [[Louisiana Territory]] from France for $15&nbsp;million, more than doubling the size of the young nation.
*[[1812]] &ndash; The [[Territory of Orleans]] becomes the 18th [[U.S. state]] under the name [[Louisiana]].
*[[1838]] &ndash; [[Nicaragua]] declares independence from the [[Central American Federation]].
*[[1863]] &ndash; A 65-man [[French Foreign Legion]] infantry patrol fights a force of nearly 2,000 Mexican soldiers to nearly the last man in [[Battle of Camarón|Hacienda Camarón]], Mexico.
*[[1864]] &ndash; [[American Civil War]]: [[Confederate States of America|Confederate]] forces led by General [[Edmund Kirby Smith|E. Kirby Smith]] [[Battle of Jenkins' Ferry|attack]] [[Federal government of the United States|federal]] troops retreating across the [[Saline River (Ouachita River tributary)|Saline]] at [[Jenkins' Ferry Battleground State Park|Jenkins' Ferry]], Arkansas.<ref>{{cite book |last=Bearss |first=Edwin C. |author-link= Edwin C. Bearss |date=1967 |chapter=Chapter V: The Confederates Fail to Destroy Stele's Army at Jenkins' Ferry |title=Steele's Retreat From Camden and the Battle of Jenkins' Ferry |others=Arrangement with the Grant County Chamber of Commerce |location=Little Rock, Arkansas |publisher=Arkansas Civil War Centennial Commission |pages=114-169 |oclc=1843035}}</ref>
*[[1871]] &ndash; The [[Camp Grant massacre]] takes place in [[Arizona Territory]].
*[[1885]] &ndash; [[Governor of New York]] [[David B. Hill]] signs legislation creating the [[Niagara Reservation]], New York's first state park, ensuring that [[Niagara Falls]] will not be devoted solely to industrial and commercial use.
*[[1897]] &ndash; [[J. J. Thomson]] of the [[Cavendish Laboratory]] announces his discovery of the [[electron]] as a [[subatomic particle]], over 1,800 times smaller than a [[proton]] (in the atomic nucleus), at a lecture at the [[Royal Institution]] in London.<ref>{{Cite journal|title=Ninety years around the atom|first=Christine|last=Sutton|journal=New Scientist|date=8 January 1997|page=49}}</ref>
*[[1900]] &ndash; [[Hawaii]] becomes a [[Territory of Hawaii|territory]] of the United States, with [[Sanford B. Dole]] as [[Governor of Hawaii|governor]].