In 1776, the first college fraternity was organized at the College of William and Mary. This fraternity was known as Phi Beta Kappa. The idea of an honorary scholarship society embodied in Phi Beta Kappa took hold and spread among the elite university across the nation. In 1873, six men banded together to form a "society to promote morality, learning, and culture" and created what would become Phi Sigma Kappa today. Our founders are Jabez William Clay, Frederick George Campbell, Joseph Franklin Barret, Xenos Young Clark, William Penn Brooks, and Henry Hague. The organization that they created was named by the three cryptic characters that cannot be pronounced, but outsiders called "T, Double T, T upside-down."

In 1878, in order to tie Alumni with the undergraduates, a Grand Chapter was organized. The official name of Phi Sigma Kappa was also adopted that year after four years of debate and the aid of seven different committees.

37 years after the founding of Phi Sigma Kappa, another fraternity known as Phi Sigma Epsilon was founded at Kansas State Normal College. The seven founders of Phi Sigma Epsilon are Raymond Victor Bottomly, W. Roy Campbell, W. Ingram Forde, Humphrey Jones, Robert C. Marley, Orin M. Rhine, and Fred M. Thompson. This new society, due to opposition from different sources, remained an underground organization until 1912 and still faced opposition until 1913 when they were officially recognized on campus.

In 1984, Phi Sigma Epsilon National President James Whitfield was approached by the Grand President of Phi Sigma Kappa with the suggestion that the two fraternities merge into one. On August 14, 1985, after many negotiations, the two fraternities merged at the 50th general convention of Phi Sigma Kappa.