John Adams (October 30, 1735 – July 4, 1826) was an American politician. He was elected second President of the United States (1797–1801) after serving as America's first Vice President (1789–1797) for two terms. He is regarded as one of the most influential Founding Fathers of the United States.

Adams came to prominence in the early stages of the American Revolution. As a delegate from Massachusetts to the Continental Congress, he played a leading role in persuading Congress to adopt the United States Declaration of Independence in 1776. As a representative of Congress in Europe, he was a major negotiator of the eventual peace treaty with Great Britain, and chiefly responsible for obtaining important loans from Amsterdam.

Adams's revolutionary credentials secured him two terms as George Washington's vice president and his own election as the second president. During his one term as president, he was frustrated by battles inside his own Federalist party against a faction led by Alexander Hamilton, and he signed the controversial Alien and Sedition Acts. The major accomplishment of his presidency was his peaceful resolution of the Quasi-War crisis with France in 1798.

After Adams was defeated for reelection by Thomas Jefferson, he retired to Massachusetts. He and his wife Abigail Adams founded an accomplished family line of politicians, diplomats, and historians now referred to as the Adams political family. His achievements have received greater recognition in modern times, though his contributions were not initially as celebrated as other Founders'.