Alpha Delta Phi

Alpha Delta Phi (ΑΔΦ, also Alpha Delt, or ADPhi) is a Greek-letter social college fraternity and the fourth-oldest continuous Greek-letter fraternity in the United States and Canada. Alpha Delta Phi was founded on October 29, 1832 by Samuel Eells at Hamilton College and includes former U.S. Presidents, Chief Justices of the U.S. Supreme Court and U.S. Senators among its 50,000+ alumni. Today, the name refers to both the all-male fraternity and the Alpha Delta Phi Society, which separated from the fraternity in 1992 and permits co-educated chapters. The Fraternity and the Society are both derived from Eells's vision for a "literary society," with each chapter upholding its literary tradition. The Dartmouth College chapter was the inspiration for National Lampoon's Animal House.

Alpha Delta Phi was the first fraternity to establish a chapter west of the Allegheny Mountains when it formed a chapter at Miami University in 1835. This chapter inspired the formation of three national fraternities at Miami in the 19th Century. Alpha Delta Phi was also a charter member of the North-American Interfraternity Conference (formerly known as the National Interfraternity Conference) (NIC), and a Brother of Alpha Delta Phi, Hamilton W. Mabie (Williams College, class of 1867), was the first President of the NIC.

For Yale University's campus, Alpha Delta Phi ranked first among all of the university's fraternities. It was brothers of Alpha Delta Phi that were mostly tapped to join the university's top-ranked senior society Skull and Bones. Issues with the number of Alpha Delta Phi's tapped for Skull and Bones also led to the creation of Yale's second society Scroll and Key.