 During the Vietnam War, the United States employed riverine artillery due to the difficulty of transporting and emplacing artillery pieces in marshy areas.The formation of a riverine task force (composed of 2d Brigade of the 9th Infantry Division and the U.S. Navy River Assault Flotilla 1) increased the importance of artillery support in riverine areas, and fixed locations near river areas proved unsatisfactory.In December 1966, 1st Battalion, 7th Artillery positioned M101A1 105mm howitzers aboard LCM-6 landing craft, with the intent that the craft be towed to a supported area and moored to a riverbank.