Dr. J.B. Robertson was one of several Lyon County residents who served in the armed forces in World War I, either stationed in the United States or fighting in the trenches in Europe. When the United States entered World War I, Dr. Robertson was the first one to enlist from the Lyon-Lincoln county medical society. He was given the rank of captain. Thirty days after enlisting, he was ordered to training camp, Ft. Riley in Kansas, later transferred to Camp Dodge, then to Ft. McKenzie in Wyoming to take charge of Post Hospital where he served until camp was discontinued. After the camp was discontinued, he transferred to Camp Lewis where he was stationed until his discharge in 1919. After his discharge, he returned to Cottonwood to resume his medical practice.