Warren K. Hillyard was born at Mount Union, Henry County, Iowa on September 27, 1885 and moved to Orange County, California in 1900.
Warren Hillyard graduated from the University of California at Berkeley with a B.S. in Engineering in 1911. After college, he worked 3 years in Mexico doing irrigation work for the Culiacan Land Company. In 1914, he as appointed Orange County chief deputy county surveyor.
During World War I, Mr. Hillyard enlisted and was commissioned as first lieutenant and assigned to the Twenty-seventh Engineers, a mining regiment.
Mr. Hillyard then served as chief deputy in the Orange County Surveyor’s Office from 1919 until 1921. In 1922, he was elected County Surveyor, and was subsequently re-elected numerous times. Mr. Hillyard retired as County Surveyor in 1955.