1800s

{| align=right cellpadding=3 id=toc style="margin-left: 15px;"\n|- \n| align="center" | Centuries:
18th century - 19th century - 20th century

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\n|-\n| align="center" colspan=2 | Decades:
1770s 1780s 1790s - 1800s - 1810s 1820s 1830s\n|- \n| align="center" colspan=2 | Years:
1800 1801 1802 1803 1804 1805 1806 1807 1808 1809\n|}\nEvents and Trends\n* Beginning of the Napoleonic Wars (1803 - 1815).\n* Semaphore is adopted by navies. World Leaders\n* Emperor Napoleon I (France)\n* Emperor Francis II (Holy Roman Empire)\n* Pope Pius VII\n* Emperor Alexander I (Russia)\n* King George III, (United Kingdom)\n* President John Adams (United States)\n* President Thomas Jefferson (United States) \n\n\n\n\n\n\n\n\n\n\n\n\n\n