Southeast Missouri State University started as a Normal School in 1873. Little is written about mathematics at the school until 1897 when B. F. (Peggy) Johnson became the mathematics instructor. He was the "mathematics department" with an instructor in another discipline occasionally filling in. His tenure lasted until his retirement in 1940 when Dr. Russell Michel was hired to replace him. During the next several decades the school made the transition from a Normal School to a Teachers College. In 1946 the name "Southeast Missouri State College" was adopted and the mathematics department truly became a department, going from a one-person staff to several staff members when two more full-time instructors were added. The department chair, Dr. Russell Michel (1940 - 1975), was the first Ph.D. in mathematics to teach at Southeast. He led the department from a teachersâ€™ training institution mentality into meeting the needs of a more comprehensive institution, then finally, to the threshold of a graduate degree-granting department within a regional university before his retirement in 1975. Thus, for a period of almost 80 years, the Department of Mathematics was guided by just two individuals.

In the post war period, Southeast Missouri State College continued to expand, offering three bachelors degrees that were typical of the period: the Bachelor of Arts degree (BA), the Bachelor of Science degree (BS) and the Bachelor of Science in Education degree (BSEd). The differences in the degrees were traditional, but all three offered a major in mathematics consisting of at least 25 hours in mathematics. Other math requirements for degrees were: five hours of mathematics required on the BS degree for all majors, two and half hours of college arithmetic required of all elementary education majors for the BSE degree and 15 hours of mathematics for all BS degrees with a major in the natural sciences.

These limited requirements, compared to today's degree requirements, meant that many degrees were granted to graduates without benefit of a single mathematics course at the collegiate level. Indeed, it was possible that graduates with a BSE or BA from Southeast Missouri State College during this era did not even have a bona fide high school mathematics course since there were high schools not requiring a basic algebra mathematics course for graduation. Admission requirements were simply a high school certificate with at least one unit of mathematics.

In 1957 the Bachelor of Science in Business Administration (BSA) was added to the college curriculum requiring five hours of mathematics among other courses. A fourth full-time staff member was added to accommodate the increased enrollment in mathematics courses by students pursuing this degree. This person, Dr. Harold Hager, later became the third chair of the mathematics department in 1976.

Great changes were abroad in higher education and at Southeast Missouri State College in the 1960s. Due in part to the emphasis placed on increased education in mathematics and the sciences by the federal government and one of its agencies, the National Science Foundation, new interest and needs in mathematics increased rapidly. To meet the challenges, new staff and courses were added to the Southeast Missouri State College mathematics curriculum.

From 1962 to 1969, 14 new faculty members were added for a total staff of 19, though only three of these had completed a doctoral degree when hired. Five of the others later completed a Ph.D. Most of the new staff had some high school teaching experience; indeed it was a desired qualification. Surprisingly, most of these individuals did not leave for other positions, but stayed on during the tenure of their teaching careers.

In 1961 the curriculum consisted of two remedial (no credit) courses, nine junior college courses and seven senior college courses which included analytic geometry and calculus III, two modern geometry courses, theory of equations, differential equations, modern algebra and analytical mechanics. It could be considered a minimal curriculum designed primarily for secondary teachers and was typical of the programs developed at teachers colleges in the 1930s and 1940s. By 1969 new courses and new emphases in mathematics had filtered into the curriculum. A series of three courses (eight hours total) for elementary education majors had been installed: a course in data processing, one in computer programming and one in finite mathematics were on the books. A senior level probability and statistics course, numerical analysis, linear algebra and matrices, mathematics seminar and advanced calculus were also available. Gone was the old theory of equations course as well as some of the initial courses like college arithmetic and remedial algebra.

Dr. Harold Hager served as chair of the Department of Mathematics until his retirement in 1995, thus ending a 98-year span with only three administrators. Dr. Victor Gummersheimer became the fourth chair in 1995 and retired in 2009. Dr. Tamela Randolph became the fifth chair in 2009.

By 1975, state law allowed the regional universities to offer graduate degrees on their own, and a master's degree with a major in mathematics was offered by the department for the first time. The first graduate degree in mathematics was awarded in 1976. Since that time approximately 100 degrees have been conferred. Graduate assistantships were available by 1977. Initially, most of the candidates for graduate degrees were secondary teachers in mathematics. This trend has continued to the present day. The graduate assistants have primarily been used as teachers of lower division and remedial courses.

The Department of Mathematics moved into its present building, then called North Hall of Science, in 1963. They were the only faculty with offices in the building though the classrooms were shared with other departments in the science division. In 1981 an addition to the building was constructed which allowed the Department of Computer Science to have offices and classrooms in the facility. This addition, made possible by a donor, was responsible for the renaming of the entire expanded structure to be renamed Johnson Hall in recognition of the first chair of the department. In 1996, with the completion of Dempster Hall nearby, the Department of Computer Science moved to that location, leaving the Department of Mathematics as the only tenant in the building save for one suite of offices. Currently, all of the classes offered by the Department of Mathematics are held in the building, though several sections of mathematics classes regularly used other facilities for classroom space before 1996.