De Lamar Jensen was a historian of early modern Europe and a faculty member of the history department at Brigham Young University.

He received his BA from BYU and his MA and PhD from Columbia University. He taught at New York University before becoming a professor of history at BYU in 1957. While at BYU, he served as chairman of the Department of History, dean of the Honors Program, and director of Study Abroad programs. He was a contributing editor for Foundation for Reformation Research, worked on the editorial committee for Sixteenth Century Journal, and was editor of Forums in History from 1973 to 1976. A scholar of international stature, he has written numerous widely acclaimed articles, and nine books, including such notables as The Renaissance World; Renaissance Europe: Age of Recovery and Reconciliation; and Reformation Europe: Age of Reform and Revolution. His Church callings have included serving as missionary in Mexico and Guatemala, in Chile, and as mission president in Peru; and as bishop and high priests group leader.

He and his wife, Mary, have five children, twenty grandchildren, and six great-grandchildren.