Epsilon Tau Pi (ΕΤΠ) Fraternity was founded in 1999 at the University of Dayton in Dayton, Ohio. Its objective is to provide a collegiate fraternity for Eagle Scouts at universities and colleges in the United States.

Epsilon Tau Pi fraternity was founded by Michael Hammes and Michael A. Mahon, who, with six other students at the University of Dayton, became the founding members of the Alpha chapter. All eight were Eagle Scouts, which became the focus of the new organization. This group of eight formally commenced operation of Alpha chapter on April 28, 1999; this date is celebrated by the fraternity as its national Founder's Day.

In 2001, the Alpha chapter authorized the formation of a five-member national executive board. The board serves to support and bolster the expansion of the fraternity, as well as to support existing chapters.

In 2003 the fraternity began to hold convocations every other year, where alumni and collegiate members alike could meet and conduct fraternity business. Officers and alumni delegates to the national executive board are elected at the convocation.

The fraternity was incorporated in Ohio on January 21, 2006.

The Epsilon Tau Pi Foundation, a charitable and educational 501(c)(3) organization, was registered on December 19, 2011, to provide scholarship assistance.

While not a member of the Association of College Honor Societies, Epsilon Tau Pi has aspects of both an honor society and service fraternity and is characterized by regular projects undertaken for local communities.

The fraternity was formed with several goals in mind. Foremost, the fraternity dedicated itself to upholding the high ideals of Scouting's Eagle rank. The fraternity enables its members to participate in and promote service to others, to Scouting, the community, their university, and the fraternity itself. Members of the fraternity must maintain strict academic standards, in addition to participation in individual, group, and chapter-wide service projects.