Northern Illinois University (NIU) is a public university located in DeKalb, Illinois. It was founded on May 22, 1895 by Illinois Governor John P. Altgeld as a satellite campus for the Illinois State Normal School (now Illinois State University), located in Normal, Illinois. The DeKalb campus was originally called Northern Illinois State Normal School. Today named Northern Illinois University, it has become an independent public university, and has grown into a comprehensive teaching and research institution with a student enrollment of more than 25,000—larger even than its parent school. NIU is one of 216 universities in the United States that is a member of the National Association of State Universities and Land-Grant Colleges (NASULGC). NIU is the second largest university in the state of Illinois after University of Illinois at Urbana Champaign.

NIU's main campus is located about 65 miles (104 km) west of Chicago. The DeKalb campus can be easily accessed via I-88 which runs east and west from Chicago. Illinois Route 38, also known as Lincoln Highway, runs along the southern border of the NIU campus. NIU also operates satellite centers in Hoffman Estates, Naperville, Rockford, and Oregon, Illinois.

Over the past three decades NIU has undergone tremendous expansion, adding more programs to enhance its academic pedigree, such as the establishment of the NIU College of Law in the early 1980s. Today, the university is composed of seven degree-granting colleges that together offer 54 undergraduate majors and 74 graduate programs, including 10 Ph.D. programs, doctoral degrees in Education and the Juris Doctor. With this growth, NIU has been recognized in the US News rankings as a "National University", that is, a university which grants a variety of doctoral degrees and strongly emphasizes research. The same publication ranks NIU as a "fourth tier" school, meaning that it is currently in the bottom 25 percent of schools within the National University category.