My dad joined the navy in 1944. After he pissed off his Navy chief in boot camp, he was assigned to what he called the Fleet Marines. Whenever I try and look up fleet marines it always tries to give me info on the regular marines. He said his fleet marine force was involved in doing diversionary attacks during invasions of several pacific islands. On his service record for the time period it says NSO Navy 926. Any info out there on Naval Fleet Marines or NSO Navy 926?
The 'Fleet Marine Force' was the WW2 designation for what we now typically refer to as 'the Marines'. It took this designation in the years between WW1 and the start of WW2, when it was realized that Japans designs on the Pacific would result in the need for a more specialized force, capable of amphibious operations. From Western Pacific Operations HISTORY OF U. S . MARINE CORPS OPERATIONS IN WORLD WAR II, vol iv
By 1927, a Joint Army-Navy Board recommended that the Marine Corps, in keeping with its close association with the Navy, be given special preparation for the conduct of amphibious warfare.
...recommendations were approved and thus was created on 7 December 1933 the Fleet Marine Force with headquarters at Quantico, Virginia, an event that was to be described as perhaps "the most significant development within the Marine Corps ."
The linked article has an entire chapter which goes in depth on the background and formation of the Fleet Marines.
Concerning other parts of your question, comments by sempaiscuba point out that the NSO designation can indicate Naval Supply Officer. Part of the organizational information on pg 24 of the above pdf includes:
...recommended the creation of Headquarters, Amphibious Troops, Pacific, to include I Marine Amphibious Corps, II Marine Amphibious Corps, an Army Corps, along with Defense Troops, Expeditionary Troops Artillery, and the Service of Supply, Amphibious Troops Pacific .
So we see indications of the inclusion of a supply unit within the Fleet Marines organizational structure.
In reference to the 926 number you ask about, the military uses numeric codes to designate locations, and these can be looked up in numerous locations.The 926 designation is listed here as:
- 926 SF Guam, Marianas Islands
(the SF indicated fleet post office San Francisco, so Pacific Fleet)
In the comments you also queried concerning other designations you found :
'ratings held AS S2c S1c'
These are essentially the ranks your father held. You can find some info here showing what insignia and the progression of the enlisted ranks. The ranks you list represent are shown as:
- AS Apprentice Seaman
- s2c Seaman Second Class
- s1c Seaman First Class