Where is the Second Marine Division located? They fall under the command of the 1st Marine Regiment and the 1st Marine Division. What was the first Marine Corps battalion?ġst Battalion 1st Marines (1/1) is an infantry battalion in the United States Marine Corps based out of Camp Pendleton, California, consisting of anywhere from 800 to 2,000 Marines and Sailors, but the number fluctuates depending on the Battalion's mission. A battalion usually contains two to five organic companies (batteries in the artillery), with a total of 500 to 1,200 Marines in the battalion. The battalion headquarters is supported by a headquarters and service company (battery). It ranks above first lieutenant and below major. Air Force (USAF), captain (abbreviated 'CPT' in the USA and 'Capt' in the USMC and USAF) is a company grade officer rank, with the pay grade of O-3. › Second battalion first marines vietnamįrequently Asked Questions What is USMC rank?.