John Marcus Oseth

John Marcus Oseth, (81), of Denton, TX, died on May 18th, 2025 at 8:40 PM. He is survived by his wife of 59 years, Marilyn, daughter Catherine Blankenau of Valley View, TX, daughter Deborah Oseth Lanham of Nokesville, VA, son John Oseth of Denver, CO, brother Stephen Oseth of Winchester, VA, seven grandchildren, and three great grandchildren. He is preceded in death by his brother, James. John was born on January 17, 1944, to an Army family. His father, a West Point graduate and career infantry officer, fought in Europe during WWII. Postwar, the family’s postings included Adak, Alaska; a military academy on Long Island, NY; Oswego, NY (while his father served in the Korean War); the US Military Academy at West Point, NY; Carlisle Barracks, PA; and Fontainebleau, France. John was graduated from Paris American High School in France, where he and his future wife, Marilyn Grundmann, became “steadies.” They dated throughout his college years and were married in 1965. John was educated at Georgetown University (B.A. and M.A.) and Columbia University (J.D., M. Phil., and Ph.D.). At Georgetown he was also commissioned as an Army officer, and he began active duty after graduating from Columbia Law School. He served for 20 years and was selected ahead of most peers for promotion to the rank of Colonel. While earning his Ph.D., John authored Regulating U.S. Intelligence Operations, A Study in Definition of the National Interest, a book that discusses the lack of supervision of America’s intelligence agencies; its crucial points are still poignant today. His Army career included assignments with infantry units in the Republic of Korea and Republic of Vietnam and with an intelligence element in Japan. He also taught American foreign policy and international relations at West Point. Thereafter he had Washington, DC, assignments that included a Military Assistantship at the U.S. Information Agency and an Army War College fellowship at a civilian “think tank.” At the Pentagon he then served as chief of plans and strategy for the Army’s senior intelligence officer and as Special Assistant to the Chairman of the Joint Chiefs of Staff. Upon retiring from the Army in 1989, John accepted an attorney position at the Washington, DC, office of Paul, Hastings where he worked on international trade and government contract matters. In 1994 he left law practice to take a position at the University of Nebraska, as Senior Advisor to the Chancellor of the Kearney campus. He later also served as Vice Chancellor for Student Affairs. He retired from the University in 2010, when he and Marilyn moved to Denton, TX. John was a multi-sport athlete in his youth and engaged actively in physical fitness activities throughout his life. In his Texas retirement, he enjoyed frequent golf outings with friends and daily gymnasium workouts. He and Marilyn loved travelling and particularly enjoyed many river cruises with friends and family in Europe. He will be interred with full military honors at Arlington National Cemetery, near the graves of his maternal and paternal grandparents, his parents, and his brother.

John Marcus Oseth

January 17, 1944 - May 18, 2025