Events January–March January 1 The legislative union of Great Britain and Ireland is completed under the Act of Union 1800, bringing about the United Kingdom of Great Britain and Ireland, and the abolition of the Parliament of Ireland. Giuseppe Piazzi discovers the asteroid and dwarf planet Ceres. January 3 – Toussaint Louverture triumphantly enters Santo Domingo, the capital of the former Spanish colony of Santo Domingo, which has become a colony of Napoleonic France. January 31 – John Marshall is appointed Chief Justice of the United States. February 4 – William Pitt the Younger resigns as Prime Minister of the United Kingdom. February 9 – The Treaty of Lunéville ends the War of the Second Coalition between France and Austria. Under the terms of the treaty, all German territories left of the Rhine are officially annexed by France while Austria also has to recognize the Batavian, Helvetian, Cisalpine and Ligurian Republic. February 17 – 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. February 27 – Washington, D.C. is placed under the jurisdiction of the United States Congress. March 4 – Thomas Jefferson is sworn in as the third President of the United States. March 10 – The first census is held in Great Britain. The population of England and Wales is determined to be 8.9 million, with London revealed to have 860,035 residents. 1.5 million people live in cities of 20,000 or more in England and Wales, accounting for 17% of the total English population. March 14 – Henry Addington becomes First Lord of the Treasury and Chancellor of the Exchequer, effectively Prime Minister of the United Kingdom. March 21 – Battle of Alexandria in Egypt: British troops defeat the French, but the British commander, Sir Ralph Abercromby, dies later of a wound received in the action. March 23 – Tsar Paul I of Russia is murdered; he is succeeded by his son Alexander I. April–June April 2 – War of the Second Coalition – First Battle of Copenhagen: The British Royal Navy, under Admiral Sir Hyde Parker, forces the Royal Dano-Norwegian Navy to accept an armistice. Vice-Admiral Horatio Nelson leads the main attack, deliberately disregarding his commander's signal to withdraw. He is created a Viscount on May 19; Denmark-Norway is forced to withdraw from the Second