A notable career in the House of Delegates (1776–79), the lower house of the legislature, followed. There Jefferson took over leadership of the “progressive” party from Patrick Henry, who relinquished it to become Governor. Highlights of this service included revision of the State laws (1776–79), in which Jefferson collaborated with George Wythe and Edmund Pendleton; and authorship of a bill for the establishment of religious freedom in Virginia, introduced in 1779 but not passed until 7 years later.

Although hampered as Governor (1779–81) by wartime conditions and constitutional limitations, Jefferson proved to be a weak executive, even in emergencies hesitating to wield his authority. When the British invaded the State in the spring of 1781, the situation became chaotic. On June 3, while the legislature was meeting in Charlottesville because the redcoats held Richmond, Jefferson recommended the combining of civil and military agencies under Gen. Thomas Nelson, Jr., and virtually abdicated office. The next day, British raiders almost captured him and a group of legislators he was entertaining at Monticello. Although later formally vindicated for his abandonment of the governorship, the action fostered a conservative takeover of the government and his reputation remained clouded for some time.

Jefferson stayed out of the limelight for 2 years, during which time his wife died. In 1783 he reentered Congress, which the next year sent him to Paris to aid Benjamin Franklin and John Adams in their attempts to negotiate commercial treaties with European nations. During his 5-year stay, Jefferson succeeded Franklin as Minister to France (1785–89), gained various commercial concessions from and strengthened relations with the French, visited England and Italy, absorbed European culture, and observed the beginnings of the French Revolution.

The University of Virginia in 1826, the year of the death of founder Jefferson.

In the years that followed, interspersed with pleasant interludes at Monticello, Jefferson filled the highest offices in the land: Secretary of State (1790–93), Vice President (1797–1801), and two-term President (1801–9). Ever averse to political strife, he occupied these positions as much out of a sense of civic and party duty as personal ambition. Aggravating normal burdens and pressures were his bitter feuds with Alexander Hamilton on most aspects of national policy, and the vindictiveness of Federalist attacks. Jefferson took considerable satisfaction, however, from his many accomplishments. Among these was the cofounding with James Madison of the Democratic-Republican Party, which in time drove the Federalists out of power.

Physically and mentally exhausted, in 1809 Jefferson retired for the final time to Monticello. He retained his health and varied interests and corresponded with and entertained statesmen, politicians, scientists, explorers, scholars, and Indian chiefs. When the pace of life grew too hectic, he found haven at Poplar Forest, a retreat near Lynchburg he had designed and built in 1806–19. His pet project during most of his last decade was founding the University of Virginia (1819), in Charlottesville.

Painfully distressing to Jefferson, however, was the woeful state of his finances. His small salary in public office, the attendant neglect of his fortune and estate, general economic conditions, and debts he inherited from his wife had taken a heavy toll. He lived more frugally than was his custom in an attempt to stave off disaster and sold off as many of his lands and slaves as he could. But when a friend defaulted on a note for a large sum, Jefferson fell hopelessly into debt and was forced to sell his library to the Government. It became the nucleus of the Library of Congress.

Jefferson died only a few hours before John Adams at the age of 83 on July 4, 1826, the fiftieth anniversary of the adoption of the Declaration of Independence. For his tombstone at Monticello, ignoring his many high offices and multitudes of other achievements, he chose three accomplishments that he wanted to be remembered for: authorship of the Declaration of Independence and the Virginia Statute for Religious Freedom and the founding of the University of Virginia.