William Edwin Berrett was born to Heber H. Berrett and Ellen E. Walker in Midvale, Utah on June 2, 1902. After graduating from Jordan High School, he received his bachelor's degree from the University of Utah in 1924 and worked as a principal of the LDS Seminary in Roosevelt, Utah. In 1926, while working on his law degree at the University of Utah, he married Eleanore Louise Callister in the Salt Lake Temple.

After graduating with a law degree, Berrett worked in a variety of positions between 1935-1947. This included being an editor for the Church Education System's curriculum development department, an author of two books ("The Restored Church" and "Readings in LDS Church History"), a special prosecutor for Utah's Office of Price Administration, an assistant U.S. Attorney in Alaska, opening a private practice in Salt Lake City, and serving as a member of the Deseret Sunday School Union's General Board. In 1947, he was hired by Brigham Young University to serve as a faculty member in two departments (Church History and the ROTC) and was shortly after appointed to serve as the Vice President of BYU and the CES in 1953. He continued to serve in the Seminary and Institute programs of the Church of Jesus Christ of Latter-day Saints until they were separated from BYU in 1965, and after serving as the head of Seminaries, Institutes, and all the non-BYU Church-run colleges, he finally retired in 1972 to work on a three-volume history of the Church Educational System which was later published in 1988 as the one-volume history "A Miracle in Week-day Education." This all happened while he and his wife raised their four children.

After retirement, Berrett finished his life serving as a patriarch in The Church of Jesus Christ of Latter-day Saints. December 2, 1993, he passed away in Utah.