
At the beginning of the American Revolution, Jefferson served in the Continental Congress, representing Virginia. He then served as a wartime Governor of Virginia from 1779 to 1781. After the war ended, Jefferson served as a diplomat in Paris in 1784 initially as a commissioner to help negotiate commercial treaties. In May 1785, he became the United States Minister to France (essentially an Ambassador).
Jefferson was also the first United States Secretary of State from 1790 to 1793 during the very first cabinet in the administration of President George Washington. He resigned the office and with his close friend James Madison he organized the Democratic-Republican Party. He was elected Vice-President in 1796 at a time when the office was the prize for the candidate who finished second in the presidential election. When President John Adams passed the Alien and Sedition Acts as a means of silencing his administration's critics, Jefferson and Madison secretly wrote the Kentucky and Virginia Resolutions, which formed the basic manifesto for states' rights.
Jefferson was elected President of the United States in the very close election of 1800. As President his administration purchased the Louisiana Territory from France in 1803, and sent the Lewis and Clark Expedition to explore the new west. His second term was more problematic. With Britain at war with Napoleon, he tried using economic warfare against them, but his embargo laws did more damage to American trade and the economy. Jefferson has often been rated in scholarly surveys as one of the greatest presidents, but some historians have criticized him for his failure to oppose slavery.
Jefferson was a very intelligent man, and had a variety of interests. Once, at a dinner of Nobel prize winners, President John F. Kennedy quipped, "I think this is the most extraordinary collection of talent, of human knowledge, that has ever been gathered at the White House - with the possible exception of when Thomas Jefferson dined alone." Jefferson spoke five languages and was keenly interested in science, invention, architecture, religion and philosophy. He designed his own mansion on a 5,000 acre plantation near Charlottesville, Virginia, which he named Monticello. His helped found the University of Virginia in his post-presidency years. He even wrote his own version of the New Testament, known as the Jefferson Bible.
As a tobacco planter, Jefferson owned hundreds of slaves throughout his lifetime. Like many of his contemporaries, he viewed Africans as being racially inferior. Although he was a slave owner, he was a leading American opponent of the international slave trade, and as President he signed the Act Prohibiting Importation of Slaves on March 2, 1807.
After Martha Jefferson, his wife of eleven years, died in 1782, Thomas remained a widower for the rest of his life. In 1802 allegations surfaced that he was also the father of his house slave Sally Hemings' children. In 1998, DNA tests revealed a match between her last child and the Jefferson male family line. The paternity of these children remains a matter of debate among historians.

Jefferson' health began to deteriorate and by June 1826 he was confined to bed. His death was from a combination of illnesses and conditions including uremia, severe diarrhea, and pneumonia. Jefferson died on July 4, 1826, the fiftieth anniversary of the Declaration of Independence, and a few hours before John Adams. Jefferson wrote his own epitaph, which reads:
HERE WAS BURIED THOMAS JEFFERSON
AUTHOR OF THE DECLARATION OF AMERICAN INDEPENDENCE
OF THE STATUTE OF VIRGINIA FOR RELIGIOUS FREEDOM
AND FATHER OF THE UNIVERSITY OF VIRGINIA.