Ernest Marvin Espelie was born on June 22, 1904 in Stoughton, Wisconsin. He graduated from Luther College in 1931, before earning both a bachelors degree and master's degree in library science from the University of Michigan in 1932 and 1935. Espelie worked as a librarian at the University of Michigan (1935-1937), Concordia College-Moorhead (1937-1938), and the U.S. Coast Guard Academy (1938-1958). In 1958, he became a librarian at Augustana College - Rock Island, where he continued until his retirement in 1974 as Professor and Emeritus Librarian. During his time at Augustana, he oversaw the microfilming of Swedish-American newspapers, church records, and fraternal society records that led to the establishment of the Swenson Swedish Immigration Research Center in 1981. He was awarded the Alumni Distinguished Service Award in 1963 from Luther College and made a Knight of the Royal Order of Vasa by the King of Sweden in 1975. He served on the Board of the Vesterheim Museum of Norweigan-American History, and belonged to a number of cultural and professional societies.

Espelie married Mary Belle Whitten in 1933. They had three children: M. Solveig, Mary, and Karl. He passed away on August 6, 1994.