In response to a specification requesting a modern individual fighting knife design for the U.S. Marines, ordnance and quartermaster officials requested submissions from several military knife and tool suppliers to develop a suitable fighting and utility knife for individual Marines, using the U.S. Navy Mark 1 utility knife and existing civilian hunting/utility knives such as Western's L77 as a basis for further improvements.[1] Working with Union Cutlery, USMC Colonel John M. Davis and Major Howard E. America contributed several important changes, including a longer, stronger blade, the introduction of a small fuller to lighten the blade, a peened pommel (later replaced by a pinned pommel), a straight (later, slightly curved) steel crossguard, and a stacked leather handle for better grip.[1][2] The blade, guard, and pommel were coated with a non-reflective matte phosphate finish instead of the brightly polished steel of the original prototype.[1] The design was given the designation of "1219C2" (although commonly known as the Ka-Bar).[1] Notably, the Ka-Bar used a thicker blade stock than that of the USN Mark 1 utility knife, and featured a stout clip point.[1] After extensive trials, the Ka-Bar prototype was recommended for adoption.[21] The Marines' Quartermaster at the time initially refused to order the knives, but his decision was overruled by the Commandant.[7][8][9] The Marine Corps adopted the Ka-Bar on November 23, 1942.[2]
The Ka-Bar proved easy to manufacture; the first production run was shipped by Camillus Cutlery Company on January 27, 1943.[2] After the U.S. Navy became disenchanted with blade failures on the USN Mark 1 utility knife, the latter service adopted the Ka-Bar as the US Navy Utility Knife, Mark 2.[22] The Marine Corps in turn re-designated the Ka-Bar as either the USMC Mark 2 Combat Knife, or simply the Knife, Fighting Utility. In naval service, the knife was used as a diving and utility knife from late 1943 onward, though the stacked leather handle tended to rot and disintegrate rapidly in saltwater.
Two USMC officers using, in accord with service tradition, a Ka-Bar knife to lift a serving of cake they have just cut, in a Marine Corps birthday ceremony on a flight line in Pakistan.
The Marine Corps issued Ka-Bar fighting utility knife throughout Marine forces, with early deliveries going primarily to elite formations. In late 1943 the Ka-Bar replaced the Marine Raider Stiletto in service, a change welcomed by the Marines of Col. Edson's 1st Raider Battalion, who found the Raider stiletto ideal for silent killing but of little use for anything else.[18] As the knife went into large-scale production, the Marines issued the Ka-Bar Fighting Utility knife to reconnaissance and engineering units and to any Marine armed with the M1911 pistol, M1 carbine, BAR, or crew-served machine gun (rifle-armed Marines were typically issued a bayonet). Marines were often issued knives with "U.S.N. Mark 2" markings when Navy-issued Ka-Bar knives were all that was available.[2] By 1944 the Ka-Bar knife was issued to virtually any Marine in the combat branches who desired one, and was in use by Marine Corps close combat instructors for training new recruits.[23] Unlike the prior Marine Raider stiletto, Marines were taught to use their new knife primarily as a slashing weapon in the initial phases of hand-to-hand combat.[24]
As its new name implied, the "Knife, Fighting Utility" was designed from the outset as a dual-purpose knife: it was both an effective combat knife and a utility tool, well-suited to the type of jungle warfare encountered by Marines in the Pacific theater.[23] This dual-purpose design resulted in some initial criticism of the pattern as being less than ideal for knife fighting, but combat experience of returning veterans as well as reports from the battlefield dispelled doubts about its combat effectiveness.[23][25]
After the Second World War, the U.S. Navy and Marine Corps continued to use the Ka-Bar Fighting Utility knife. In addition to military contract knives, the knife was produced for the civilian market, and the pattern enjoyed some popularity as a general-purpose hunting and utility knife.[26]