In 1958, the Archdiocese of Hartford purchased 30 acres of land on Wampanoag Drive, West Hartford with an eye to future development. Two years later, the Most Rev. Henry J. O'Brien, D.D., Archbishop of Hartford, announced that a high school would be built on this tract of land to serve the students in the surrounding parishes. On September 24, 1961, the Most Rev. John F. Hackett, D.D., officiated at the formal dedication of Northwest Catholic High School. Eight members of the order of Dominican Sisters of St. Mary of the Springs were among the first faculty. The first class graduated in June 1965.
The Rev. Bradford Colton was principal from 1961-68 and guided the school during its founding years. He was succeeded by Rev. William F. O'Keefe in 1968 and Sr. Doris Regan, O.P., in 1977. In 1985, Rev. Henry C. Frascadore was named the first president of Northwest Catholic, while Sr. Doris remained as principal. Dr. Michael Griffin replaced Fr. Frascadore as president in 1996, and Mrs. Margaret Williamson became principal in 2000. In June 2005, upon Dr. Griffin's departure, Mrs. Williamson became acting president and principal, and in June 2006, Matthew O’N. Fitzsimons became president. In July 2009, Mrs. Williamson replaced Mr. Fitzsimons and served as Principal/Chief Administrator until February 2013. At that time, David C. Eustis, Jr. was named President/Chief Administrator.
In December 1971, the Commission on Independent Secondary Schools granted Northwest Catholic institutional membership in the New England Association of Colleges and Secondary Schools (NEASC) for a period of ten years. This accreditation has since been renewed in 1981, 1991, 2001, and 2011.
In 1989, Northwest Catholic High School was recognized by the U.S. Department of Education as an Exemplary School, and in 2011, Margaret Williamson received the Catholic Secondary Education Award from the National Catholic Education Association (NCEA) for outstanding leadership -- one of only six people nationwide to receive this award that year.