Thomas Jefferson (April 13 April 2] 1743 – July 4, 1826) was an American Founding Father, the principal author of the Declaration of Independence (1776), and the third President of the United States (1801–1809). He was a spokesman for democracy, and embraced the principles of republicanism and the rights of the individual with worldwide influence. At the beginning of the American Revolution, he served in the Continental Congress, representing Virginia, and then served as a wartime Governor of Virginia (1779–1781). In May 1785, he became the United States Minister to France and later the first United States Secretary of State (1790–1793) serving under President George Washington. In opposition to Alexander Hamilton's Federalism, Jefferson and his close friend, James Madison, organized the Democratic-Republican Party, and later resigned from Washington's cabinet. Elected Vice President in 1796 in the administration of John Adams, Jefferson opposed Adams, and with Madison secretly wrote the Kentucky and Virginia Resolutions, which attempted to nullify the Alien and Sedition Acts.
Elected president in what Jefferson called the "Revolution of 1800", he oversaw acquisition of the vast Louisiana Territory from France (1803), and sent out the Lewis and Clark Expedition (1804–1806), and later three others, to explore the new west. Jefferson doubled the size of the United States during his presidency. His second term was beset with troubles at home, such as the failed treason trial of his former Vice President Aaron Burr. When Britain threatened American shipping challenging U.S. neutrality during its war with Napoleon, he tried economic warfare with his embargo laws, which only impeded American foreign trade. In 1803, President Jefferson initiated a process of Indian tribal removal to the Louisiana Territory west of the Mississippi River, having opened lands for eventual American settlers. In 1807 Jefferson drafted and signed into law a bill that banned slave importation into the United States.