Omega Psi Phi Fraternity, from its beginning, was created as an undergraduate organization. However, while some chapters were established on college campuses - like Alpha chapter at Howard University in 1911 and Beta chapter at Lincoln University in 1914, others were established to service multiple institutions within a larger jurisdiction – starting with Gamma chapter in 1916 for colleges and universities in the city of Boston, and including Harvard University, Boston University and the Massachusetts Institute of Technology. But whether established on a college or university campus, or within a city, no permanant chapter established before 1920 was established with a designation as undergraduate or graduate - they were established only as chapters. As more Brothers graduated from college, and as more graduates were either initiated as members of chapters or became "elected active" honorary members of chapters, the desire to continue associations with the Fraternity beyond the college years grew. Those graduated brothers continued to be active members of the chapters in existence, but their individual focus as a graduate was understandably different than their undergraduate brethren in these "mixed chapters". This directly led to need for graduate chapters, and the need for the classification of both undergraduate and graduate chapters in the Fraternity.
Iota Chapter was established on August 17, 1920 in Atlantic City, NJ as the first graduate chapter of the Fraternity for Brothers who lived in or relocated to Atlantic City – mainly due to an abundance of job and career opportunities available there for Blacks. Iota Chapter did also initiate several prominent members of the Atlantic City community – with the first two being H.A. Warner and G.D. Brooks – but for unknown reasons Iota Chapter became inactive and was shuttered by the Fraternity by best accounts in May 1922 after less than 2 years in existence.
By 1923 there were a large number of Black students attending the several colleges and universities in and around Chicago, and the increasing number of younger Omega men coming to Chicago to take up studies and seek employment made it desirable for those Brothers to organize an undergraduate chapter. Sigma chapter had already been established in Chicago in 1921 as an undergraduate chapter, but it had been established for students at the University of Chicago and Northwestern University, not as a city-wide undergraduate chapter.
These aspiring undergraduate Brothers, including: J.A. Berry, G.T. Perry, D. Jones, F.W. Crawford, C. Washington, J.N. Nabritt Jr. and J.E. Eubanks, along with the assistance of Benjamin W. Clayton, a graduate Brother in Sigma chapter, submitted a request to both the Supreme Council and the Central Representative of the Grand Basileus Bro. Raymond Hill, for an undergraduate chapter in Chicago because, “the graduate chapter should grow out of the undergraduate chapter and not vice versa.” This sentiment alludes to the heavy influence the graduate members of Sigma chapter had on the chapter's operation and activities.
It should be noted that graduated Brothers that lived in or moved to the Chicago area also became members of Sigma undergraduate chapter after its formation, making this a mixed chapter (of what is believed to have been composed of mostly graduate members) – just like many other chapters within the Fraternity in 1922 due to the lack of both graduate and undergraduate chapters in general. Then on October 1, 1923 the Supreme Council designated the Sigma chapter undergraduate charter solely for undergraduates at the University of Chicago and established a new chapter - Sigma Omega - as the first graduate chapter for the city of Chicago. The graduated Brothers that were in the undergraduate Sigma chapter now had a graduate chapter to affiliate with.
Less than 2 weeks later on October 12, 1923, and in response to the request from the undergraduate Brothers in the city of Chicago without a chapter, the Supreme Council changed the dormant Iota Chapter graduate charter designation to undergraduate, then transferred that charter from Atlantic City to the University of Chicago. The undergraduate Sigma chapter charter (believed to have been inactive for a lack of eligible members) was transferred by the Supreme Council from the University of Chicago to McGill University in Montreal, Quebec, Canada on December 15, 1923 - becoming the first International chapter of the Fraternity. After a brief period between 1923 and 1924, the Iota Chapter's University of Chicago campus jurisdiction was then expanded to be a Chicago city-wide undergraduate chapter.
Iota Chapter continued in operation at the University of Chicago as a city-wide undergraduate chapter for about 30 years until a point in the early 1950’s the chapter became inactive because it did not constitutionally have enough members to operate as a chapter in good standing within the Fraternity. Later in the decade Sigma Omega chapter supported the efforts of Chicago’s undergraduate Brothers by initiating a series of undergraduate lines between 1954 and 1957 with the intent to re-activate Iota Chapter, culminating with the May 27, 1957, “Application for Undergraduate Chapter Charter” and the September 9, 1957 petition. These efforts resulted in the Iota Chapter being recognized by the Fraternity as being in good standing, and the charter being re-activated and re-designated, first as a city-wide undergraduate chapter, then shortly afterward as an Intermediate chapter designated for both graduate and undergraduate members.
Sigma Omega chapter as a graduate chapter and Iota Chapter as an intermediate chapter continued as the only chapters of the Fraternity in Chicago until Epsilon Eta chapter was established as the second undergraduate chapter chartered in Chicago at Chicago State University on February 18, 1978 and Kappa Mu chapter was established as the third undergraduate chapter chartered in Chicago at the University of Illinois at Chicago in 1983.
On March 1, 1987 Rho Gamma Gamma chapter was chartered as the second graduate chapter established in Chicago. Then, after a twelve-year inactive period that began in 1983, again for a lack of members to constitutionally operate as a chapter of the Fraternity in good standing, Iota Chapter was re-activated on February 12, 1995, retaining its Intermediate chapter status. Shortly after the February reactivation, Iota Chapter was returned to its original designation as a graduate chapter on July 12, 1995 creating a third graduate chapter in Chicago. Rho Mu Mu chapter was the fourth graduate chapter established in Chicago on September 6, 2011.