Leonard Illies was born on November 30, 1926 to Benedict and Barbara Illies in Lidgerwood, ND. He grew up on the family homestead with 12 of his brothers and sisters and a step-brother. The family moved to a farm north of Bagley in 1945.

Leonard enlisted in the Army in Bemidji in April, 1946 and was accepted into Military Service at Fort Snelling on April 3, 1946. He was sent to Fort Buckley, Colorado for Basic Training and transferred to Fort Lowry Colorado.

After Colorado, Leonard was transferred to Fort Worth, Texas Army Air Field to work as a Fire Fighter. He worked there until his discharge on October 2, 1947.

After his Honorable Discharge in 1947, he returned home. His family had moved to Fosston, MN. He married Inez Stenseng of Bagley in 1949, and they raised a family of five children. They lived in Fosston until 1962, when they moved to Bagley. Leonard became owner/ operator of Illies Oil Co. until his death on August 24, 2001.