|Motto||Connecticut's Public Liberal Arts University|
|President||Dr. Elsa Nuñez|
|221 (FT); 315 (PT)|
|Campus||Suburban, 182 acres (0.74 km2), Map|
Navy Blue and
|Athletics||NCAA Division III|
|Affiliations||Little East Conference|
|Sports||17 varsity teams |
|Mascot||Willi the Warrior|
Eastern Connecticut State University (Eastern, Eastern Connecticut, Eastern Connecticut State, or ECSU) is a public liberal arts 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.
Eastern Connecticut State University is a member of the Connecticut State Colleges and Universities, with governance provided by the Connecticut Board of Regents for Higher Education.
The Connecticut General Assembly established the Willimantic State Normal School in 1889.  As a normal school, the institution trained schoolteachers.  The first class was of thirteen female students, who attended classes on the third floor of the Willimantic Savings Institute.   The first male student entered in 1893. 
In 1890, the Town of Windham deeded 6 acres (24,000 m2) to the State of Connecticut for construction of a new campus for the school.  The larger campus was completed in 1895.  The first dormitory, Burr Hall, opened in September 1921.  The institution was renamed Willimantic State Teachers College in 1937, after it began granting bachelor's degrees.   The original Normal School building was destroyed in a fire and replaced by Shafer Hall, which was dedicated in 1946. 
The State College created its first graduate program (in education) in 1953.  After expanding its programs and campus, it became Eastern Connecticut State College in 1967, and Eastern Connecticut State University in 1983.  
Academically, the university is organized into three schools, the School of Arts and Sciences, the School of Education and Professional Studies, and the School of Continuing Education. Graduate study programs offered through the School of Education and Professional Studies and include Education, Teacher Certification, and Organizational Management.
The Institute for Sustainable Energy was opened in 2001 and focuses on sustainable energy education, serving as a source for sustainable energy information, assistance in sustainable energy policy making, and assistance in implementing sustainable energy solutions.  The institute is located at 182 High Street. The current director is William Leahy.
In 2012 Eastern had a stationary phosphoric acid fuel cell, known as the PureCell System Model 400, installed on the west side of its Science Building.  Eastern will use 100 percent of the energy produced by the fuel cell system to provide a majority of the power required for the Science Building, while maximizing the use of the heat output available. Under a 10-year Energy Services Agreement (ESA) with ClearEdge Power, the installation was made possible by a federal American Recovery and Reinvestment Act (ARRA) grant through CEFIA. 
87 percent of first-year students, and 60 percent of all full-time undergraduates live in college housing. The campus is separated into first-year halls and upperclassman halls. All students with sophomore status and higher are eligible to live in upperclassman halls.  There are six first-year halls, five upperclassman halls and two sets of apartments.
Eastern offers more than 80 student organizations in which students can participate, including athletic, political, cultural, artistic and communication clubs. The Campus Activity Board sponsors many of the events on campus, including movies, concerts, comedians, and trips. The campus newscast is ETV. The Student Government Association is the liaison between the student body and university administration and each residence hall has a student council that plans events and trips for hall residents.
The Lantern is notable because in the 2000s it became the very first student-run newspaper at a college or university in the United States to completely abandon its printed issues in favor of a website. Paper issues of The Campus Lantern have since been brought back.
In 2013 a cartoon with a homosexual theme published in The Lantern sparked so much controversy amongst students, faculty, and administration at ECSU that it was reported on by major news outlets nationwide. 
In the late 1990s and early 2000s The Lantern published two joke issues per school year, one per semester: "The Jack-O-Lantern" in October to coincide with Halloween and "The Campus Latrine" in April to coincide with April Fool's Day.
Eastern's sports teams are known as the "Warriors" and are represented by a logo depicting a shield superior to two crossed swords. The university is a member of the NCAA Division III, the Little East Conference and the Eastern College Athletic Conference.  Men's varsity sports include baseball, basketball, cross country, lacrosse, soccer, and indoor and outdoor track and field. Women's varsity sports include basketball, cross country, field hockey, lacrosse, soccer, softball, swimming, indoor and outdoor track and field, and volleyball.
Intramural sports include men's and women's tennis league, co-ed indoor and outdoor soccer, co-ed dodgeball, men's and women's flag football, men's and women's volleyball, co-ed softball, ultimate frisbee league, men's and women's basketball league, co-ed floor hockey, wiffle ball tournament, golf. Club sports include competitive cheerleading, fencing club, football club, ice hockey club and rugby club.
The men's baseball team won the NCAA Division III national championship four times (1982, '90, '98, '02). The women's softball team won national championships five times (1981 ( AIAW Div. III), '82, '85, '86, and '90 − NCAA).
Eastern's campus, which is spread over 182 acres (0.74 km2), is divided into three areas: South Campus, North Campus, and the University Sports Complex. South Campus is the historic part of the University and includes buildings such as Burr Hall, the school's first dormitory, which dates back to 1921. North Campus, the more modern part of the University, is home to the library, the fine arts instructional center, and the student center.
The university has undergone a number of construction projects in recent years. Past projects have included the construction of a new administration building, a new library, five new residence halls, the conversion of Burr Hall from a women-only residence hall to a co-ed residence, renovation and expansion of the Student Center, the construction of a state-of-the-art Science Building, and the Child and Family Development Center. A new public safety building opened in August 2009. A new parking garage was built next to the other parking garage in the north part of campus, having opened in January 2011 and artificial turf was installed on the soccer/field hockey/lacrosse field during the summer of 2009. A new main entrance to the University was constructed in summer 2011 and a new softball field opened in March 2012. Projects being planned for the future include a fine arts building and the second phase of the track project which includes installing bleachers and lighting. One of the major driving forces behind Eastern's construction projects is to make more green space for students.
- Chimamanda Ngozi Adichie '01 - Nigerian writer included in the 2011 edition of The Best American Short Stories.
- Pat Boyd '03 – (D-50) Connecticut State Representative
- Christopher D. Coutu - Army National Guard Officer and (R-47) Connecticut State Representative
- William A. Cugno '84 - Adjutant General of the Connecticut National Guard 1999 - 2005.
- Edward Gaffney - Michigan State Representative (2003–2008)
- David W. Gay - Adjutant General of the Connecticut National Guard 1992 - 1999, Chairman of the Citizen's Ethics Advisory Board of the Office of State Ethics as of October 1, 2011
- Victoria Leigh Soto - Sandy Hook Elementary School teacher, who heroically protected her students from harm during a massacre that occurred on December 14, 2012. She was one of the 26 individuals killed during the shooting.
- Susan Wilson '73 - Author of seven novels, including her 2010 New York Times best seller One Good Dog.
- "Graphic Standards MANUAL" (PDF). Eastern Connecticut State University. Retrieved 26 September 2014.
- "Eastern's History of Excellence". Eastern Connecticut State University. 2012.
- Dick Curland, Historically Speaking: Eastern began as 'normal school' to prepare teachers, Norwich Bulletin (November 26, 2017).
- "Institute for Sustainable Energy Mission Statement". Archived from the original on September 18, 2006. Retrieved August 25, 2006.
- "Housing and Residential Life". Archived from the original on September 14, 2006. Retrieved August 25, 2006.
- "Fast Facts". Archived from the original on April 27, 2006. Retrieved August 25, 2006.