James Madison's accomplishments include writing the Federalist Papers, playing a major role in the creation of the U.S. Constitution and serving as the fourth president of the United States of America. During his tenure as the latter, he declared war on Great Britain, leading the War of 1812.
Madison represented Virginia during the Constitutional Convention in 1787, and his proposal of the so-called Virginia Plan became a central part of the present American Constitution, leading to his nickname, "Father of the Constitution. He also wrote the Federalist Papers with John Jay and Alexander Hamilton to persuade the states to ratify the Constitution. In 1789, he then proposed a series of amendments to the Constitution granting rights ranging from freedom of speech to protection against unreasonable searches, leading to what is now called the Bill of Rights.
In 1791, Madison helped found the Democratic-Republican Party with Thomas Jefferson, and when Jefferson became president in 1801, Madison served as his secretary of state. During this time, he helped Jefferson secure the Louisiana Purchase, expanding America's borders past the Mississippi. After Jefferson's two terms were completed, he ran for office himself and became president in 1809. During that time, he successfully guided America through the aforementioned War of 1812. His second term ended in 1817.
Madison also found the American Colonization Society, an organization dedicated to returning slaves to Africa, in 1816 with Robert Finley, James Monroe and Andrew Jackson. While Madison died in 1836, the society went on to successfully fulfill its mission with the creation of the African nation of Liberia in 1847.