The Marine Corps utility cap came into being as a component of the revised utility uniform developed and issued in 1944. The new utility uniform was upgraded to include features to make it more useful in the field as a combat uniform. The previous HBT utility uniform, introduced in 1941, was developed along the lines of civilian denim chore clothing of the period. HBT uniforms were, out of necessity, adopted for tropical combat wear in 1942 for lack of time and any better alternative. Early on, the uniform was usually worn with a garrison cap or fiber sun helmet. But, soon after offensive actions began in the pacific, Marines were issued the Army's HBT mechanic's cap (U.S. Army Specification PQD 18B dated 8 April 1941) for wear in the field. A right facing EGA
Shown is an enlisted man's service collar ornament, otherwise known as an EGA (Eagle Globe and Anchor) insignia. The ornaments with right facing eagles were worn on the left side of the service uniform lapel, on the left side of the garrison cap, and on the front of the Army type HBT cap. This type of EGA with an approximately 9/16 inch globe was worn from 1937 to 1955. Thereafter the design was changed to show a fouled anchor (anchor with rope). uniform collar insignia was often attached to the front center of the crown to distinguish the Marines. The practice of converting the Army cap to marine wear likely served as an inspiration for the M-1944 utility cap.

Along with a new cap, the utility uniform took on a completely new look in 1944, with spacious cargo pockets being added to both the trousers and coat. Though similar in appearance to the previously used Army model, the new Marine's cap had some notable differences. The visor was made longer offering better shielding against the sun. Also featured was a ready-made EGA in form of a heat transfer, which was applied to the front of the crown. The location of the EGA affected the positioning of the shaping darts around the crown of the cap causing them to be arranged such that the heat transfer could be applied to an uninterrupted piece of material centered at the front. The positioning of the shaping darts around the cap are keys in distinguishing the Marine cap from the Army cap.
(Point here for comparison of different cap types.)
Pictured: A comparison of the USMC M-1944 utility cap (above) and the early model U.S. Army HBT cap (below) worn my Marines throughout the war. The Marine Corps cap exhibits a longer visor when compared to the Army model. Also note the shaping darts are arranged on the Marine Corps cap on either side of the EGA and on either side of the vent holes, whereas the Army model shows darts running down the front of the cap and between the two vent holes.

M-1944 utility caps are sometimes found with the Marine's last name written boldly across the bottom of the visor. Caps marked in this way are encountered often enough to conclude that this was an approved ownership marking method. However, it is unclear whether this was a war-time or post-war practice.

The coat and trousers components of the M-1944 utility uniform continued to be manufactured and issued according to specific chest and waist measurements. However, the cap was manufactured using a simplified sizing scheme; small, medium, large, and extra large. Owing to the generic sizing, ill fitting caps were commonly tailored at the rear sweat band seam to provide a better fit.

Throughout the WWII period, the USMC continued to use a light shade of HBT for its utility uniforms. This color is often referred to as "sage green" by collectors and historians. It is unclear why the Marines continued to use this light shade HBT when developing the revised utility uniform in 1944; though it should be noted that separate camouflage patterned utility uniforms were also developed and issued alongside regular HBT utilities. In contrast, The Army and Navy darkened the color of their HBT uniforms to olive drab shade 7 in early 1943 in response to a call for uniforms offering better camouflage properties in the jungle terrain of the pacific. Then, as development of herringbone twill continued, the Army and Navy developed a joint specification for the material in 1944; JAN-C-154, Cloth, Cotton, Herringbone Twill, which called for 8.5 ounce, olive drab shade 7 material. In the fall of 1943 production of the Army's HBT cap changed over to the darker Olive drab color. This fact would have necessitated the Marine Corps' development of a HBT cap once the light shade of material was retained for the M-1944 utility uniform.

The type of herringbone twill material used in Marine Crops WWII utilities seemed to have a distinctive appearance making them easily recognizable even at a distance. While color variations were common in WWII uniforms, and Marine Corps uniforms were no exception, the majority of Marine Corps light shade HBT seemed to have a more of a grayish cast than its Army & Navy counterparts. A more obvious difference occurred in the weave pattern. USMC HBT weave tended to have more pronounced ridges in the twill weave, creating a very discernible stripping effect.