Editing 1800s (decade) (section)

===Prominent political events===
* 1800
** The unfinished [[White House]] (at the time known as the "Executive Mansion") housed its first president, [[President John Adams]], on 1 November 1800.<ref name="ThoughtCo" />
* 1801
** Under the [[District of Columbia Organic Act of 1801]], [[Washington, D.C.]], a new [[New town|planned city]] and [[Capital (political)|capital]] of the [[United States]], was placed under the jurisdiction of the [[United States Congress|U.S. Congress]].
** The [[Kingdom of Great Britain]] and the [[Kingdom of Ireland]] merge into the [[United Kingdom of Great Britain and Ireland]] in 1801.
* 1803
** United States doubles its size with territories gained from [[Napoleon Bonaparte]] in the [[Louisiana Purchase]].
** The [[Supreme Court of the United States|United States Supreme Court]] rules in [[Marbury v. Madison]], giving themselves the ability of [[Judicial review in the United States|Judicial review]], and substantially expanding the Judicial branch's power.<ref>{{Cite web |date= |title=Marbury v. Madison |url=https://www.oyez.org/cases/1789-1850/5us137 |access-date=6 November 2024 |website=Oyez}}</ref>
*1809
**The first British monarch to mark a jubilee in a significant way was [[King George III]]. The [[Golden Jubilee of George III]] on 25 October 1809 marked the forty-ninth anniversary of his accession and his entrance into the 50th year of his reign.