During what the Marine Corps named "Operation Detachment", the majority of Combat Logistics operations were handled by a little known unit in the 5th Amphibious Corps called 8th Field Depot.
A unit of the Supply Service, the 8th's primary role was to manage the flow of materiel under fire and keep units equipped with any and all essential equipment. The laundry list was limitless, from rations to medical supplies, ammunition, or communications equipment.
Throughout the 36 days of fighting, personnel from the 8th mostly fought with 5th Marine Division, though members were scattered to the lines of the 3rd and 4th Marine Divisions as well. After the initial landings when supplies were being unloaded and dispersed to respective units, Marines who at first did not have a "front line" job were thrust into combat as casualties mounted. Clerks became machine gunners, field telephone operators became demolition men, cooks became litter (stretcher) bearers...Supply Service Marines went wherever they were needed.
If you are reading this because you discovered a search result for a relative who is listed on the Company Rosters for 8th Field Depot, located here, please reach out to me via the contact page. I am constantly seeking out information on my great-uncle's personnel, and every single detail adds to the understanding of the invaluable role they contributed during the battle.