Thomas Jefferson served as the 3rd US President from 1801-1809. Some key events of his presidency included establishing the White House as the presidential residence, resolving the election tie in 1800 that led to the 12th amendment, sending Lewis and Clark on an expedition to explore the western territories, dealing with tensions with the Barbary States including the First Barbary War, and enacting economic policies like the Embargo Act and Non-Intercourse Act. Jefferson retired on July 4, 1826, dying on the same day as John Adams.