These three organizations are the oldest continuously existing Greek-letter social fraternities in North America. Union College along with Miami University (for the "Miami Triad") are considered the "Mother of Fraternities."
Other Fraternities who owe their birth to Union College include:
The Miami Triad are three fraternities that were founded at Miami University in Oxford, Ohio. These fraternities, in the order they were founded, are Beta Theta Pi (1839), Phi Delta Theta (1848), and Sigma Chi (1855). Historians of fraternities often compare the significance of the Miami Triad to the "Union Triad" of fraternities that formed at Union College in the mid 1820s.
Other national Greek organizations founded at Miami, in addition to the Triad, are Delta Zeta Sorority, founded in 1902, and Phi Kappa Tau Fraternity, founded in 1906. Because of the number of Greek organizations founded at Miami University, the school is often called Mother of Fraternities.
It is has been tradition at some campuses, such as Iowa State University, the University of Kansas, and the University of Mississippi that have local representation of each of the Miami Triad chapters, to hold an annual party, formal, or ball, (often referred to as "Miami Triad" or simply "Triad") to commerate their tie to each other and the Miami Triad's place in Greek history. This tradition has waned in recent years and some schools have transformed the celebration into to other types of events, such as the University of Kansas' Miami Triad Concert.
The Lexington Triad are three American college fraternities that came out of Lexington, Virginia during the Reconstruction period following the American Civil War.
Members of the triad include Alpha Tau Omega, founded in Richmond, Virginia in 1865 by students from Virginia Military Institute (VMI) in Lexington; the Kappa Alpha Order, founded in 1865 at Washington and Lee University; and Sigma Nu, founded in 1869 at VMI. These organizations maintain ties to the area today, as the national headquarters of both Kappa Alpha and Sigma Nu are located in Lexington.
The members of the Triad are sometimes also grouped as part of the Virginia Circle, which includes two or three other fraternities founded in Virginia, roughly during that period: Kappa Sigma and Pi Kappa Alpha from the University of Virginia and sometimes Sigma Phi Epsilon from Richmond College.
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