Eastern Connecticut State University is a public university in Willimantic, Connecticut. Founded in 1889, it is the second-oldest campus in the Connecticut State University System and third-oldest public university in the state. Eastern is located on Windham Street in Willimantic, Connecticut, on 182 acres (0.74 km2) 30 minutes from Hartford, lying midway between New York City and Boston. Although the majority of courses are held on the main campus, select classes take place at Manchester Community College, Capital Community College, and a satellite center in Groton.

Willimantic is a census-designated place located in Windham, Connecticut. Previously organized as a city and later as a borough, Willimantic is currently one of two tax districts within the Town of Windham. Willimantic is located within Windham County and the Southeastern Connecticut Planning Region. Known as "Thread City" for the American Thread Company's mills along the Willimantic River, it was a center of the textile industry in the 19th century. Originally incorporated as a city in 1893, it entered a period of decline after the Second World War, culminating in the mill's closure and the city's reabsorption into the town of Windham in the 1980s.