Jefferson Duo

The term Triad is used to designate certain historic groupings of seminal college fraternities in North America.

The Union Triad is a group of three early fraternities founded at Union College in Schenectady, New York: the Kappa Alpha Society (established 1825), Sigma Phi (1827) and the Delta Phi (1827). No formal organization exists.

These three organizations are among the oldest existing Greek-letter social fraternities in North America. Phi Beta Kappa and the Jefferson Literary and Debating Society both predate them as Greek-lettered organizations, but the former is an honor fraternity and the latter, as the name suggests, a literary and debating organization.

Other fraternities which owe their birth to Union College include Psi Upsilon (1833), Chi Psi (1841) and Theta Delta Chi (1847). Collectively, these many foundings earned Union College the title Mother of Fraternities.

The Miami Triad refers to three fraternities founded at Miami University in Oxford, Ohio in the 19th century: Beta Theta Pi (1839), Phi Delta Theta (1848), and Sigma Chi (1855). Historians of fraternities often compare the significance of the Miami Triad to that of the earlier Union Triad.

Delta Zeta sorority was founded at Miami University in 1902, and Phi Kappa Tau fraternity in 1906. Delta Sigma Epsilon sorority began there in 1914, merging in 1956 with Delta Zeta. These numerous Greek organization foundings cause some to refer to the school also as the Mother of Fraternities.

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