1803

1803 (MDCCCIII) was a common year starting on Saturday of the Gregorian calendar and a common year starting on Thursday of the Julian calendar, the 1803rd year of the Common Era (CE) and Anno Domini (AD) designations, the 803rd year of the 2nd millennium, the 3rd year of the 19th century, and the 4th year of the 1800s decade. As of the start of 1803, the Gregorian calendar was 12 days ahead of the Julian calendar, which remained in localized use until 1923.

Millennium:	2nd millennium
Centuries:	18th century – 19th century – 20th century
Decades:	1770s  1780s  1790s  – 1800s –  1810s  1820s  1830s
Years:	1800 1801 1802 – 1803 – 1804 1805 1806

1803 in other calendars

Gregorian calendar	1803 MDCCCIII
French Republican calendar	11–12
Ab urbe condita	2556
Armenian calendar	1252 ԹՎ ՌՄԾԲ
Assyrian calendar	6553
Balinese saka calendar	1724–1725
Bengali calendar	1210
Berber calendar	2753
British Regnal year	43 Geo. 3 – 44 Geo. 3
Buddhist calendar	2347
Burmese calendar	1165
Byzantine calendar	7311–7312
Chinese calendar	壬戌年 (Water Dog) 4499 or 4439     — to — 癸亥年 (Water Pig) 4500 or 4440
Coptic calendar	1519–1520
Discordian calendar	2969
Ethiopian calendar	1795–1796
Hebrew calendar	5563–5564
Hindu calendars
- Vikram Samvat	1859–1860
- Shaka Samvat	1724–1725
- Kali Yuga	4903–4904
Holocene calendar	11803
Igbo calendar	803–804
Iranian calendar	1181–1182
Islamic calendar	1217–1218
Japanese calendar	Kyōwa 2 (享和２年)
Javanese calendar	1729–1730
Julian calendar	Gregorian minus 12 days
Korean calendar	4136
Minguo calendar	109 before ROC 民前109年
Nanakshahi calendar	335
Thai solar calendar	2345–2346
Tibetan calendar	阳水狗年 (male Water-Dog) 1929 or 1548 or 776     — to — 阴水猪年 (female Water-Pig) 1930 or 1549 or 777

Events

• January 4 – William Symington demonstrates his Charlotte Dundas, the "first practical steamboat".
• January 30 – Monroe and Livingston sail for Paris to discuss, and possibly buy, New Orleans. They end completing the Louisiana Purchase.
• February 21 – Edward Despard and six others are hanged, drawn and quartered for plotting to assassinate king George III and to destroy the Bank of England
• February 24 – The Supreme Court of the United States, in Marbury v. Madison, establishes the principle of judicial review.
• March 1 – Ohio is admitted as the 17th U.S. state, retroactive from August 7, 1953.
• April 30 – Louisiana Purchase made by the United States from France.
• March 12 – Port Gibson, MS is chartered
• May 18 – The United Kingdom redeclares war on France after France refused to withdraw from Dutch territory.
• July 4 – The Louisiana Purchase is announced to the American people.
• July 5 – The convention of Artlenburg leads to the French occupation of Hanover (which had been ruled by the British king).
• July 23 – Robert Emmet's uprising in Ireland begins
• July 26 – The wagonway between Wandsworth and Croydon is opened, being the first public railway line of the world.
• August 3 – British begin Second Anglo-Maratha War against Sindhia of Gwalior
• September 20 – Irish rebel Robert Emmet is executed
• September 23 – The Battle of Assaye in India – British-lead troops defeat Maratha forces
• October 20 – Senate ratifies the Louisiana Purchase Treaty, doubling the size of the United States.
• November 30 – At the Cabildo building in New Orleans, Spanish representatives Governor Manuel de Salcedo and the Marqués de Casa Calvo, officially transfer Louisiana Territory to French representative Prefect Pierre Clément de Laussat (just 20 days later, France had transferred the same land to the United States as the Louisiana Purchase).

• Aargau, Graubünden, St. Gallen, Thurgau, the Ticino, Vaud become Swiss cantons.
• France – the Livre Tournois (Tours Pound) is replaced by the Franc.
• William Osgoode, Chief Justice of Lower Canada, rules that slavery is inconsistent with British Law.

Ongoing events

• Napoleonic Wars (1799-1815)

Births

for more information, see Category:1803 births.

Deaths

for more information, see Category:1803 deaths.