William Denison Lyman was born in Portland, Oregon in 1852. His early education was received at Tualatin Academy and Pacific University, where he graduated from the scientific course in 1873. He later was awarded his A.B. from Williams College in 1877. In September of the same year he became teacher of English Literature, History, and Oratory at Pacific University, where he remained for ten years.

After spending a year at Fresno, California, endeavoring to start a raisin ranch, he subsequently teaching at the University of New Mexico in Santa Fe, he came to Whitman College in November, 1888. Here he remained continuously, except during the year 1890-91, when he was engaged in an effort to start a new college at Spokane. At Whitman he taught History regularly and served as department Head. In addition, he at various times taught English Literature, Rhetoric, Oratory, Political Economy, Political Science, Latin, Greek, Elementary Geology, Physiology, and Astronomy.

He was the author of many newspaper and magazine articles and of several books, among them The Columbia River; it's history, it's myths, it's scenery; it's commerce; Lyman's History of Old Walla Walla County: embracing Walla Walla, Columbia, Garfield, and Asotin counties; and Indian Myths of the Northwest

Lyman was also known as a mountain climber, having climbed most of the highest peaks of the Northwest and writing descriptions of them. He had just been awarded the title of Professor Emeritus when he died suddenly in June 1920.