Kansas; the Richard Nixon Presidential Library and Museum in Yorba Linda, California; and the Ronald Reagan Presidential Library and Museum in Simi Valley, California. These gravesites are open to the general public. Political affiliation Political parties have dominated American politics for most of the nation's history. Though the Founding Fathers generally spurned political parties as divisive and disruptive, and their rise had not been anticipated when the U.S. Constitution was drafted in 1787, organized political parties developed in the U.S. in the mid-1790s nonetheless. They evolved from political factions, which began to appear almost immediately after the Federal government came into existence. Those who supported the Washington administration were referred to as "pro-administration" and would eventually form the Federalist Party, while those in opposition joined the emerging Democratic-Republican Party. Greatly concerned about the very real capacity of political parties to destroy the fragile unity holding the nation together, Washington remained unaffiliated with any political faction or party throughout his eight-year presidency. He was, and remains, the only U.S. president never to be affiliated with a political party. Since Washington, every U.S. president has been affiliated with a political party at the time of assuming office. The number of presidents per political party at the time they were sworn into office (arranged in alphabetical order by last name) are: Timeline of presidents The following timeline depicts the progression of the presidents and their political affiliation at the time of assuming office. See also Outline of American politics Notes References Further reading Ayton, Mel Plotting to Kill the President: Assassination Attempts from Washington to Hoover (Potomac Books, 2017), United States Balogh, Brian and Bruce J. Schulman, eds. Recapturing the Oval Office: New Historical Approaches to the American Presidency (Cornell University Press, 2015), 311 pp. Lang, J. Stephen. The Complete Book of Presidential Trivia. Pelican Publishing. 2001. Graff, Henry F., ed. The Presidents: A Reference History (3rd ed. 2002) online, short scholarly biographies from George Washington to William Clinton. Greenberg, David. Republic of Spin: An Inside History of the American Presidency (W. W. Norton & Company, 2015). xx, 540 pp. bibliography Han, Lori Cox. The Presidency (ABC-CLIO, 2021). wide-ranging reference book. Han, Lori Cox, ed. Hatred of America's Presidents: Personal Attacks on the White House from Washington to Trump (ABC-CLIO, 2018). Holzer, Harold. The Presidents Vs. the Press: The Endless Battle Between the White House and the Media--from the Founding Fathers to Fake