19th century

===1801–1850===
* [[1801]]: The [[Kingdom of Great Britain]] and the [[Kingdom of Ireland]] merge to form the [[United Kingdom of Great Britain and Ireland|United Kingdom]].
* [[1802]]: The [[Wahhabi]]s of the [[Wahhabi sack of Karbala|First Saudi State sack Karbala]].
* [[1803]]: [[William Symington]] demonstrates his ''[[Charlotte Dundas]]'', the "first practical steamboat".
* [[1803]]: The [[Wahhabi]]s of the [[First Saudi State]] capture [[Mecca]] and [[Medina]].
* [[1804]]: [[Austrian Empire]] founded by [[Francis II, Holy Roman Emperor|Francis I]].
* [[1804]]: [[World population]] reaches 1 billion.
* [[1805]]: The [[Battle of Trafalgar]] eliminates the French and Spanish naval fleets and allows for British dominance of the seas, a major factor for the success of the [[British Empire]] later in the century.
* [[1805]]–[[1848]]: [[Muhammad Ali of Egypt|Muhammad Ali]] modernizes [[Egypt]].
[[File:StamfordRaffles.jpeg|thumb|upright|[[1819]]: 29 January, [[Stamford Raffles]] arrives in Singapore with [[William Farquhar]] to establish a trading post for the [[East India Company|British East India Company]]. 8 February, The treaty is signed between Sultan Hussein of Johor, Temenggong Abdul Rahman and Stamford Raffles. Farquhar is installed as the first Resident of the settlement.]]
* [[1810]]: The [[Humboldt University of Berlin|University of Berlin]] was founded. Among its students and faculty are [[Georg Wilhelm Friedrich Hegel|Hegel]], [[Karl Marx|Marx]], and [[Otto von Bismarck|Bismarck]]. The German university reform proves to be so successful that its model is copied around the world (see [[History of European universities#European university models in the 19th and 20th centuries|History of European research universities]]).
* [[1814]]: [[Elisha Collier]] invents the [[Flintlock]] [[Revolver]].
* [[1814]] : February 1 Eruption of [[Mayon Volcano]] 
* [[1815]]: April, [[Mount Tambora]] in [[Sumbawa]] island erupts, becoming the largest [[volcanic eruption]] in [[recorded history]], destroying [[Tambora culture]], and killing at least 71,000 people, including its aftermath. The eruption created [[global climate]] anomalies known as "[[volcanic winter]]".<ref name="Oppenheimer2003">{{cite journal|last=Oppenheimer|first=Clive|title=Climatic, environmental and human consequences of the largest known historic eruption: Tambora volcano (Indonesia) 1815|journal=Progress in Physical Geography|volume=27|issue=2|year=2003|pages=230–259|doi=10.1191/0309133303pp379ra|bibcode=2003PrPG...27..230O |s2cid=131663534}}</ref>
* [[1816]]: [[Year Without a Summer]]: Unusually cold conditions wreak havoc throughout the Northern Hemisphere, likely influenced by the 1815 explosion of [[Mount Tambora]].
* [[1816]]–[[1828]]: [[Shaka]]'s [[Zulu Kingdom]] becomes the largest in [[Southern Africa]].
* [[1819]]: The [[Colombia|Republic of Colombia]] ([[Gran Colombia]]) achieves independence after [[Simón Bolívar]]'s triumph at the [[Battle of Boyacá]].
* [[1819]]: The modern city of [[Singapore]] is established by the [[British East India Company]].
* [[1820]]: Discovery of [[Antarctica]].
* [[1820]]: [[History of Liberia|Liberia]] founded by the [[American Colonization Society]] for freed American slaves.
* [[1820]]: Dissolution of the [[Maratha Empire]].
* [[1821]]–[[1823]]: [[First Mexican Empire]], as Mexico's first post-independence government, ruled by Emperor [[Agustín de Iturbide|Agustín I of Mexico]].
* [[1822]]: [[Pedro I of Brazil]] declared Brazil's independence from Portugal on 7 September. 
* [[1823]]: [[Monroe Doctrine]] declared by US President [[James Monroe]].
* [[1825]]: The [[Decembrist revolt]].
[[File:Kolman decembrists.jpg|thumb|upright|[[Decembrists]] at the [[Saint Petersburg Senate Square|Senate Square]].]]
* [[1829]]: [[Sir Robert Peel]] founds the [[Metropolitan Police Service]], the first modern police force.
[[File:Emigrants Leave Ireland by Henry Doyle 1868.jpg|thumb|upright|Emigrants leaving [[Ireland]]. From 1830 to 1914, almost 5 million Irish people went to the United States alone.]]
* [[1830]]: Anglo-Russian rivalry over Afghanistan, [[the Great Game]], commences and concludes in 1895.
* [[1831]]: November Uprising ends with crushing defeat for Poland in the [[Battle of Warsaw (1831)|Battle of Warsaw]].
* [[1832]]: The British Parliament passes the [[Great Reform Act]].
* [[1834]]–[[1859]]: [[Imam Shamil]]'s rebellion in Russian-occupied [[Caucasus]].
* [[1835]]–[[1836]]: The [[Texas Revolution]] in Mexico resulted in the short-lived [[Republic of Texas]].
* [[1836]]: [[Samuel Colt]] popularizes the [[revolver]] and sets up a firearms company to manufacture his invention of the [[Colt Paterson]] revolver, a six bullets firearm shot one by one without reloading manually.
* [[1837]]–[[1838]]: [[Rebellions of 1837]] in [[Canada]].
* [[1838]]: By this time, 46,000 Native Americans have been forcibly relocated in the [[Trail of Tears]].
* [[1839]]–[[1860]]: After the [[First Opium War|First]] and [[Second Opium War]]s, France, the United Kingdom, the United States and Russia gain many [[Treaty ports|trade and associated concessions]] from China resulting in the start of the decline of the [[Qing dynasty]].
* [[1839]]–[[1919]]: [[Anglo-Afghan War]]s lead to stalemate and the establishment of the [[Durand line]]
* [[1842]]: [[Treaty of Nanking]] cedes [[Hong Kong]] to the British.
* [[1843]]: The first [[wagon train]] sets out from Missouri.
* [[1844]]: [[Rochdale Society of Equitable Pioneers]] establish what is considered the first [[cooperative]] in the world. 
* [[1845]]–[[1849]]: The [[Great Famine (Ireland)|Great Famine of Ireland]] leads to the [[Irish diaspora]].
* [[1848]]: ''[[The Communist Manifesto]]'' published.
* [[1848]]: [[Seneca Falls Convention]] is the first [[women's rights]] convention in the United States and leads to the [[History of Women's Suffrage in the United States|battle for women's suffrage]].
* [[1848]]–[[1855]]: [[California Gold Rush]].
* [[1849]]: Earliest recorded [[Airstrike|air raid]], as Austria employs [[The Austrian balloons|200 balloons]] to deliver ordnance against [[Venice]].
* [[1850]]: The [[Little Ice Age]] ends around this time.
* [[1850]]: [[Franz Hermann Schulze-Delitzsch]] establishes the first [[cooperative banking|cooperative financial institution]].
[[File:U.S. Territorial Acquisitions.png|thumb|250px|Historical [[Territorial evolution of the United States|territorial expansion of the United States]]]]