Thomas Jefferson (April 13 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.
John Calvin Coolidge, Jr. (July 4, 1872 – January 5, 1933) was the 30th President of the United States (1923–1929). A Republican lawyer from Vermont, Coolidge worked his way up the ladder of Massachusetts state politics, eventually becoming governor of that state. His response to the Boston Police Strike of 1919 thrust him into the national spotlight and gave him a reputation as a man of decisive action. Soon after, he was elected as the 29th Vice President in 1920 and succeeded to the Presidency upon the sudden death of Warren G. Harding in 1923. Elected in his own right in 1924, he gained a reputation as a small-government conservative, and also as a man who said very little.
The Monroe Doctrine was a US foreign policy regarding Latin American countries in 1823. It stated that further efforts by European nations to colonize land or interfere with states in North or South America would be viewed as acts of aggression, requiring U.S. intervention. At the same time, the doctrine noted that the United States would neither interfere with existing European colonies nor meddle in the internal concerns of European countries. The Doctrine was issued in 1823 at a time when nearly all Latin American colonies of Spain and Portugal had achieved or were at the point of gaining independence from the Portuguese and Spanish Empires; Peru consolidated its independence in 1824, and Bolivia would become independent in 1825, leaving only Cuba and Puerto Rico under Spanish rule. The United States, working in agreement with Britain, wanted to guarantee that no European power would move in.