Upon his death in February 1999, Leonard J. Arrington left behind a legacy of scholarship and mentoring that rightly earned him the title "Dean of Mormon History." Largely because of his leadership, Mormon historical studies in the second half of the twentieth century became a viable subject in the larger discipline of American history. His book Great Basin Kingdom: An Economic History of the Latter-day Saints is still considered to be one of the classic works of Mormon history. Due to his prominent place in Mormon studies, Arrington's papers are a valuable source of information for anyone interested in Mormon history in general, but especially for those interested in the growth of the field in the twentieth century.

Leonard Arrington was born on July 2, 1917, in Twin Falls, Idaho, the second child of Noah and Edna Arrington, two devout members of the Church of Jesus Christ of Latter-day Saints (more commonly known as Mormons). Growing up on a chicken farm, Leonard first entertained thoughts of becoming a farmer himself. This desire was enhanced through his participation in the Future Farmers of America, where he served in both state and national positions. When the time for college came, Arrington chose the University of Idaho, where he had attended an FFA convention, hoping to major in agriculture. The chemistry requirements, however, soon led Arrington to change his mind and he concentrated instead on agricultural economics.

After graduating from the University of Idaho, Arrington continued his education at the University of North Carolina at Chapel Hill, where he began studies towards a doctorate in economics and began teaching classes with the aid of a Kenan Teaching Fellowship. World War II interrupted his schooling, and Arrington served overseas for the United States in both North Africa and Italy from 1943 to 1946, working first in a prisoner-of-war processing division and later performing tasks for Italy's Institute of Statistics. These years were especially difficult for Arrington since he had to be away from his wife, Grace Fort, whom he had married in the fall of 1942. Following the war, Arrington returned to the United States, where he began working as an economics professor at Utah State Agricultural College (later Utah State University) in Logan in 1946. Returning in subsequent years to the University of North Carolina to complete course work and necessary exams, he finally received his doctorate in economics in March 1952. His dissertation was entitled "Mormon Economic Policies and Their Implementation on the Western Frontier, 1847-1900." This topic led Arrington to begin studying a wide variety of issues pertaining to Mormon economic history. Following the publication of his first scholarly articles on this subject in 1951, Arrington began slowly to transform himself from an economist to a historian.

Arrington found his work at Utah State University to be very satisfying. Later in his life he would reminisce about how much he loved his years in Cache Valley and how much he enjoyed teaching and mentoring students. Arrington's professional reputation rapidly grew from his numerous articles and lectures, and in 1958 Harvard University Press published a work based on his dissertation entitled Great Basin Kingdom: An Economic History of the Latter-day Saints. The book soon became a Western American history classic, but because the press published it on the recommendation of the Committee on Research in Economic History, Arrington received no royalties from the book until 1993, when the University of Utah Press released a second edition.

During his tenure at Utah State University in the 1950s Arrington enjoyed the company of several other budding Mormon scholars, including S. George Ellsworth, a professor of history, and Eugene E. Campbell, a staff member at the LDS Church Institute in Logan. Arrington's family grew during this time with the birth of three children: James Wesley in 1948, Carl Wayne in 1951, and Susan Grace in 1954. Arrington also participated in the Church of Jesus Christ of Latter-day Saints and served in numerous leadership capacities, including second counselor in the Utah State University Stake Presidency.

From 1958 to 1959 he momentarily interrupted his Logan stay by taking his family to Italy as a Fulbright Professor of American Economics at the University of Genoa. In 1966, he again left Logan to serve as visiting professor of history at the University of California, Los Angeles, for the 1966-1967 academic school year.

In the late 1960s and early 1970s, Arrington participated in several important professional endeavors, including the establishment of the Mormon History Association (serving as its first president) and the creation of the Western Historical Quarterly, the premier academic journal of the American West. He also served as president of the Western History Association, the Agricultural History Association, and the Pacific Coast Branch of the American Historical Association. Finally, in 1972, he became Church Historian of the Church of Jesus Christ of Latter-day Saints, simultaneously receiving an appointment as Lemuel H. Redd Professor of Western History and Director of the Charles Redd Center for Western Studies at Brigham Young University.

Arrington worked as Church Historian from 1972 to 1982, when the church transferred his division to Brigham Young University, renaming it the Joseph Fielding Smith Institute for Church History. As the first (and only) professional academic to be named Church Historian, Arrington presided over a blossoming of Mormon history. His colleagues produced numerous important historical studies, and Arrington himself authored or co-authored several books, including David Eccles: Pioneer Western Industrialist (1975); Building the City of God: Community and Cooperation Among the Mormons (1976); The Mormon Experience: A History of the Latter-day Saints (1979); and Brigham Young: American Moses (1985).

At the same time, Arrington experienced numerous personal and professional frustrations, as he constantly combated a church hierarchy which did not regard the work of his department as "faith-promoting." Balancing his commitment to his profession and his loyalty to his church, Arrington frequently clashed with church authorities. Finally, the Church appointed G. Homer Durham as managing director of the division, and Durham worked constantly to ensure that the department produced "faith-promoting" history. This approach ultimately led to Arrington's release as Church Historian, Durham's appointment to that position, and the transfer of the entire Historical Department to Brigham Young University in 1982.

Arrington also battled a personal tragedy during this time. In March 1982, Grace, his wife of nearly forty years, succumbed to heart disease and passed away. Both personally and professionally bereft, Arrington turned to his role as educator and found solace in his classes at Brigham Young University. He also met and began dating Harriet Horne in 1983. After a quick courtship, the two were married on November 19, 1983. Harriet provided not only welcome companionship, but also aided Arrington's research and writing by entering drafts of his books on her computer and collaborating with him on occasion. As a result, Arrington remained a productive scholar throughout the 1980s and 1990s, publishing numerous works such as the commissioned two-volume History of Idaho, a memoir of his years as Church Historian, a biography of Utah rancher Charlie Redd, and biographies of Harold and Madelyn Silver. He also co-authored two books with his daughter, Susan Arrington Madsen, and collaborated on several projects with his step-daughter, Heidi Swinton. In addition, he continued to mentor numerous scholars in Mormon history by critiquing their manuscripts, write letters of recommendation, and provide encouraging words about their endeavors.

As Arrington grew older, he could look back on the numerous awards and honors he received for his prolific work. In 1962 he presented a well-received paper on the Topaz World War II Relocation Camp for Japanese-Americans as part of Utah State University's Faculty Honor Lecture series. In 1969 he received the David O. McKay Humanities Award from Brigham Young University. In 1986 he became the first Mormon and the first Utahn to be elected a member of the Society of American Historians, one of the highest honors bestowed upon American historians. Finally, in 1996 he was presented with the Governor's Award in the Humanities in Utah.

Arrington has also received numerous accolades for his writings. Great Basin Kingdom received the Award of Merit of the American Association of State and Local History and was also given the annual award of the Pacific Coast Branch of the American Historical Association for the best first book by a Western historian in 1958-1959. It became the first book on the Mountain West placed in the White House's presidential library. Building the City of God: Community and Cooperation Among the Mormons, co-authored with Dean May and Feramorz Y. Fox, received the Best Book Award for 1976 from the Mormon History Association, while Brigham Young: American Moses was the first recipient of the David W. and Beatrice Cannon Evans Award for a distinguished biography of a significant personality living in Mormon country during the past 150 years. It also won the Mormon History Association Best Book Award for 1985 and was nominated by the National Book Critics Circle as a distinguished work of biography.