The university was founded as East Central State Normal School in 1909, two years after Oklahoma was admitted as the 46th U.S. state. It was one of the six newly created state funded normal schools that were designed to provide four years of "preparatory" (or high school) study, followed by two years of college work towards teacher certification. The school's establishment was the product of the intense lobbying efforts of the 25,000 Club, a local booster group. The club raised funds for faculty salaries so classes could begin that fall in local churches and public school classrooms. Graduates of the normal school program received lifetime teaching certification statewide. The 1910 Oklahoma Legislature funded faculty salaries and the construction of a building on a 16-acre (65,000 m2) site donated by a Chickasaw allottee. In 1919, the normal schools were authorized by the Oklahoma Legislature to offer four years of teacher education, to offer bachelor's degrees, and were designated teachers' colleges.
Expanding beyond education degrees, in 1939 the school became East Central State College. Fifteen years later, the regional colleges were allowed to offer graduate degrees. By 1974, the state legislature renamed the state colleges, and it became East Central Oklahoma State University—a name it retained until 1985 when it gained its present name.
ECU serves around 5,000 students and is perhaps best known internationally for its cartography program, as only a few such programs exist. ECU is also home to an Environmental Health Science Program, one of only 30 programs nationally accredited by the National Environmental Health Science and Protection Accreditation Council
East Central is one of four participating institutions offering courses at the Ardmore Higher Education Center. There are also Distance Education sites located in Shawnee, OK, through the Gordon Cooper Technology Center and McAlester, OK through the Eastern Oklahoma State College. ECU offers online graduate and undergraduate courses.