Dear Ms. Clifton,
Thank you for posting your request on History Hub!
There potentially could be a copy of the marriage certificate or other documentation of the marriage in your father’s Official Military Personnel File. We suggest that you request a copy of his Official Military Personnel File (OMPF). OMPFs and individual medical reports for enlisted men of the U.S. Army who served through most of the 20th century are in the custody of NARA's National Personnel Records Center in St. Louis. However, be advised that many personnel records were destroyed in the 1973 fire. Please complete a GSA Standard Form 180 and mail it to NARA's National Personnel Records Center, (Military Personnel Records), 1 Archives Drive, St. Louis, MO 63138-1002. If there is any information requested by the form you do not know, you may leave it blank or provide estimates, however the more information you provide, the easier it will be for NPRC staff to locate the correct file. Veterans and their next of kin also may use eVetRecs to request records. See eVetRecs Help for instructions. For more information see Request Military Service Records.
Due to the COVID-19 pandemic, the NPRC was closed from March 23 through June 23, 2020. As of June 24, the NPRC entered into Phase One of a gradual reopening process. The center is currently only servicing emergency requests associated with medical treatments, burials, homeless veterans, VA Home loan guarantees, and employment opportunities. If this is urgent, please see Emergency Requests and Deadlines. We apologize for any inconvenience.
If the marriage was conducted by a military chaplain, there could be a record in the Monthly Reports and Personnel Records, 1920 - 1950 in the Records of the Office of the Chief of Chaplains (Record Group 247) that is arranged by name of the chaplain. For more information, please contact the National Archives at St. Louis (RL-SL) via email at firstname.lastname@example.org for more information. Please provide the name of the chaplain in order to search these files.
Additionally, the local German government where they were married may have a record of the marriage. See Obtaining Vital Records from U.S. Embassy and Consulates in Germany and Germany Civil Registration from FamilySearch for information about accessing German marriage records.
If the marriage was registered with the Department of State, there may be a Certificate of Witness to Marriage Abroad. Please see How to Request a Copy of a Certificate of Witness to Marriage Abroad (filed before November 9, 1989) from the Bureau of Consular Affairs for instructions on requesting copies of these.
If the American marriage was conducted in a US state and involved getting a US marriage licence, that state should have records of their marriage. See Where to Write for Vital Records from the CDC about locating American vital records.
If she lives or has lived in the United States, she also may contact the US Citizenship and Immigration Services and request her immigration records, which may include documentation of her marriage to a US citizen. See Request Records through the Freedom of Information Act or Privacy Act from the USCIS.
We hope this information is helpful. Best of luck with your family research!