A member of the Democratic-Republican Party, Monroe was the last president who was a Founding Father as well as the last president of the Virginia dynasty and the Republican Generation; his presidency coincided with the Era of Good Feelings, concluding the First Party System era of American politics. He is perhaps best known for issuing the Monroe Doctrine, a policy of opposing European colonialism in the Americas while effectively asserting U.S. dominance, empire, and hegemony in the hemisphere. He also served as governor of Virginia, a member of the United States Senate, U.S. ambassador to France and Britain, the seventh Secretary of State, and the eighth Secretary of War.
Born into a slave-owning planter family in Westmoreland County, Virginia, Monroe served in the Continental Army during the American Revolutionary War. After studying law under Thomas Jefferson from 1780 to 1783, he served as a delegate in the Continental Congress. As a delegate to the Virginia Ratifying Convention, Monroe opposed the ratification of the United States Constitution. In 1790, he won election to the Senate, where he became a leader of the Democratic-Republican Party. 