Donald B. Robertson was born and raised in Nampa, Idaho. He became interested in journalism and was the weekly proofreader for his high school newspaper. During World War II, Donald joined the Merchant Marine as a ship's purser. He then attended the University of Idaho, graduating in 1948 with a Bachelor's in Business. At the U of I, Donald continued his interest in journalism, directing photography for the Gem of the Mountains yearbook for two years, including the "Beauty" section is senior year. He was also a member of the fraternity Sigma Alpha Epsilon and journalism honorary Sigma Delta, and participated in Ski Club, the Blot Magazine, and Jr. Chamber of Commerce. After graduation, Donald married and moved to San Francisco.

After ten years working in the credit department at Shell Oil Company, Donald bought a hardware store. He retired in 1982 to devote full time to his long-held hobby of researching railroad history. Donald published the Encyclopedia of Western Railroad History between 1986 and 1998, a four volume set extensively detailing all railroads in The Desert States, The Mountain States, Oregon, Washington, and California.