Valeria F. Hilgart was born in Grafton, Wisconsin, the daughter of an excavator and World War I veteran. She attended a Catholic grade school and graduated from Grafton High School in 1942. She worked for seven years as a clerk in a gray iron foundry while attending Milwaukee Business Institute.
Hilgart enlisted in the U.S. Marine Corp on 21 July 1949. She completed six weeks of basic training and personnel administration school at Parris Island, South Carolina. Hilgart was then sent to Headquarters Marine Corps in Arlington, Virginia, where she worked as a clerk in the records service section and later in the decorations and medals department. In 1951, she attended Officer Candidate School in Quantico, Virginia, and then basic school.
From basic school Hilgart was transferred to Camp Pendleton, California, as the Executive Officer of the Women Marine Company. She was later transferred to Pearl Harbor, Hawaii, as the Commanding Officer (CO) of the Women Marine Company. She was stationed there until January 1955, when she was transferred to Headquarters Marine Corps as the CO. In 1956 she was reassigned to the 6th Marine Corps Reserve District at Headquarters Marine Corps. She was later transferred to El Toro, California, as the CO of the Women Marine Detachment there from 1958 to 1960. While in El Toro she received the rank of major.
From 1960 to 1963 Hilgart returned to Headquarters Marine Corps as the head of the candidate accounting unit. From 1963 to 1965 she worked as executive officer of the recruit training battalion at Parris Island. There she received the rank of lieutenant colonel. In 1965 she was transferred back to Headquarters Marine Corps in the recruit training battalion. She was sent to Quantico as the CO of the Women’s Officers’ School in 1967. There she created and taught a women officers’ commanding leadership course.
Hilgart was stationed in Okinawa, Japan from 1968 to 1970 and served as the personnel staff officer at Camp Butler. On September 7, 1970 she received the rank of colonel. In 1972 she was transferred to Camp Lejeune, North Carolina as the assistant chief of staff for manpower. She was sent to Marine Corps Logistic Base at Albany, Georgia, as director of personnel and administration in 1978. In 1979 she became the chief of staff of the base. In 1981 she retired for the first time after thirty years of commissioned service.
In January 1982, Hilgart was called back to active duty. While stationed at Camp Lejeune and Albany, she had negotiated contracts for civilian workers who were members of the American Federation of Government Employees (AFGE). She was called back to duty to create a consolidated contract for all AFGE units in the Marine Corps. In April of 1982 she was officially back on active duty. She was sent to Washington, D.C., where she set up an office. By December of 1982 the contract was completed. Hilgart was put back on the retired list on 31 December 1982 and officially retired from the U.S. Marine Corps in 1985.
After retiring from the service, Hilgart moved to Jacksonville, North Carolina.