Lyle Wesley Dorsett was born April 17, 1938 in Kansas City, Missouri. He received his B.A. in history (1960) and M.A. in history (1962) from the University of Kansas City. He earned his Ph.D. in history from the University of Missouri in 1965. His expertise was in urban history. His dissertation on the political machine of Kansas City Alderman Jim Pendergast was published by the Oxford University Press in 1968 under the title The Pendergast Machine. He began his teaching career at the University of Missouri. He also taught briefly at the University of Southern California and University of Colorado at Denver before joining the University of Denver faculty in 1972.

During his stay at the University of Denver, Dorsett continued his prolific writing, which resulted in several articles each year and ten books published during his stay in Denver. He was also a gifted and active teacher, achieving tenure in 1974. Several of his students went on to be collaborators on research projects. At least three students earned Ph.D.'s of their own and pursued careers as university professors.

Dr. Dorsett left the University in October, 1983, to accept a position at the Marion E. Wade Center at Wheaton College in Wheaton, Illinois. Since that time a large portion of his writings have concerned the life and philosophy of C. S. Lewis, the subject of one of the Wade Center's major collection. He has written several books on Lewis and his wife, as well as numerous articles.