Theta Chi Fraternity was founded on Thursday, April 10, 1856 at 9:00 pm on the campus of Norwich University in Norwich, Vermont by Frederick Norton Freeman and Arthur Chase, assisted by Egbert Phelps. Chase became the first president and Freeman was the first secretary. Phelps, who transferred to Union College and joined Chi Psi Fraternity, suggested the name of the organization and designed the first badge of Theta Chi, which is still in use today. The first pledges were Edward Williston and Lorenzo Potter.

Theta Chi was the first Greek Letter society to make its appearance at Norwich. It was preceded in 1853 by a secret society known as the "Regulators." This established the Alpha Chapter which later became inactive in 1960 when Norwich University abolished fraternities. In March of 1866, the Old South Barracks, the founding place of Theta Chi Fraternity at Norwich University, was completely destroyed by fire. Norwich University was relocated to Northfield, Vermont. One year later, Frederick N. Freeman died in Newburgh, New York.

 On September 8, 1881, Norwich University was reduced to 15 students and Theta Chi membership was reduced to one undergraduate member, James M. Holland. On November 19, Phil Randall and Henry Hersey were initiated, thus saving the Fraternity from extinction.

In 1890, Alpha Chapter acquired the first chapter house in Northfield, Vermont.

On February 22, 1908, the Grand Chapter of Theta Chi Fraternity was organized at Boston, Massachusetts. J. Albert Holmes was elected the first national president. On September 25, 1908, Delta Chapter was installed at Rensselaer Polytechnic Institute in Troy, New York.

The pledge button was officially adopted by the Grand Chapter on January 21, 1911. On February 28, 1912, the first edition of The Rattle was published as the newsletter of Theta Chi Fraternity. In September of 1923, the first Executive Office opened in New York City. In April of 1928, the Executive Office moved to Huntington, West Virginia. "It Is to Thee", the official flag, banner, and pennant were adopted in June of 1928. In June of 1932, the Executive Office was moved to Trenton, New Jersey. On April 14, 1942, Beta Kappa Fraternity (16 chapters) merged with Theta Chi Fraternity.

On May 20, 1950, Delta Theta Chapter was installed at the University of Toledo in Toledo, Ohio and became the 100th chapter of Theta Chi Fraternity. On February 20, 1965, Zeta Gamma Chapter was installed at the University of Alberta in Edmonton, Alberta, Canada, making Theta Chi an International Fraternity.

In June of 1990, the International Headquarters moved from Trenton, New Jersey to Indianapolis, Indiana. On April 27, 1991, Theta Chi initiated its 125,000th member.

In 1922, Twelve men formed organization known as the Gamma Sigma local fraternity; G stands for Gentlemen, S stands for scholars. The group was also known as the “cupids.”

In 1926, Theta Chi occupies first chapter house (located to the left of Smith Hall and across the street from the North East corner of the Quad)

On February 26, 1926, Hank Crisp (Theta Chi, Nu chapter, Hampden-Sydney College) persuades Paul “Bear” Bryant to come play for the University.

In April 1926, Theta Chi (National Fraternity) approved membership petition for Gamma Sigma local fraternity.

On May 7, 1926, Forty-three men were initiated into Theta Chi Fraternity.

On May 7, 1926 at 11:02 a.m., Frank Schrenk (National V.P.) handed charter to Russell A. Lewis (First Alpha Phi President).  George Catuna was the National President and Frederick Ladue was the National Secretary.  The first Alpha Phi officers were as follows:

President:                      Russell A. Lewis

Vice-President:              William Barnett

Secretary:                      George Gallacher

Treasurer:                      James Smith

First Guard:                   Harry B. Lackey

First Initiate:                  Stewary J. Lloyd  (Lloyd Hall)

In 1948, Roy Killingsworth was elected SGA President

In 1961, The new Alpha Phi chapter house was built.  Bill Thomas was the president of Alpha Phi at the time and Joseph Ross, the National President, dedicated the house.  Items brought to the new house from the old house include a Cannon from the USS Albatross (FDS9590). 

In 1962, Richard Thigpen was elected chapter President after freshman year

In 1963, Thigpen wins the Colley Award (Most Distinguished National Undergraduate)

In 1969, Dale Taylor Petitioned National for the Ladue Fund (Emergency Fund established in 1950).  The Fund is administered by the Grand Chapter for emergency use.  Dale Taylor later won the Colley Award.

In 1971, Harry B. Lackey cosigned for $25,000 note for the chapter house New Wing addition.  Marvin McConaghy, President of Alpha Phi, dedicated the new wing to Lackey.

In 1972, Marvin McConaghy wins Colley Award.

In 1973, Larry Childs becomes SGA President.

In 1976, Pete Derzis wins Colley Award.

In 1992, Thomas Howard wins Colley Award.