Births on May 31

Johann Georg Baiter, Swiss philologist and scholar (d. 1887)

Johann Georg Baiter (May 31, 1801 – October 10, 1877) was a Swiss philologist and textual critic.

1 Jan

United Kingdom of Great Britain and Ireland
The legislative union of Kingdom of Great Britain and Kingdom of Ireland is completed to form the United Kingdom of Great Britain and Ireland.
17 Feb

Thomas Jefferson
An electoral tie between Thomas Jefferson and Aaron Burr is resolved when Jefferson is elected President of the United States and Burr, Vice President by the United States House of Representatives.
23 Mar

Paul I of Russia
Tsar Paul I of Russia is struck with a sword, then strangled, and finally trampled to death inside his bedroom at St. Michael's Castle.
2 Apr

Battle of Copenhagen (1801)
French Revolutionary Wars: The British capture the Danish fleet.
10 May

Barbary pirates
First Barbary War: The Barbary pirates of Tripoli declare war on the United States of America.