| Original caption: “Front view of 240 millimeter howitzer of Battery B, 697th Field Artillery Battalion, just before firing into German held territory. Mignano area, Italy.” The M1 240 millimeter (9.4-inch) Howitzer was the largest mobile field piece used in combat by the United States Army during World War II (except for railway guns). During World War I, the United States Army determined that a 240 millimeter howitzer was needed. Approximately 300 weapons based on a French design were built even after the November armistice. The project to replace the unsatisfactory 240 millimeter M1918 dated from the mid-1920s. In 1934, it was decided to design an all new weapon to rectify the shortcomings of the French-designed World War I-era weapon. The program, prototype T1, only started in April of 1940 and the M1 was standardized in May 1943, even though mass production had already started — the new howitzer entered service in 1940. At Monte Cassino, the Allied forces had emplaced by February 22, 1944, 60 155 millimeter (6.1 inch) “Long Toms,” and 12 240 millimeter M1 Howitzers; which had a range slightly less than the Long Tom but a projectile more than 3 times as powerful. The M1 240 millimeter howitzer and the M1 8 Inch (203 millimeter) Gun were the heaviest mobile American artillery weapons. The designers had intended that both use the same mount, in line with the Ordnance Department’s policy of pairing a gun (a long-barreled cannon of high muzzle velocity) with a howitzer (a short-barreled cannon of low muzzle velocity, firing shells in a relatively high trajectory) of approximately the same caliber. Next in power in the gun-howitzer pairs were the M1 155 millimeter Gun and the M1 8 Inch (203 millimeter) Howitzer, and last were the M1 4.5 inch (114 millimeter) Gun and the M1 155 millimeter Howitzer, which were considered medium, rather than heavy, artillery. The theater had not requested the M1 240 millimeter Howitzers. Early in October 1943, Lieutenant General Jacob L. Devers (September 8, 1887 – October 15, 1979) the Deputy Commanding General of North African Theater of Operations, United States Army (NATOUSA) had asked the War Department for 55 tubes for 155 millimeter guns, needed because the guns had been fired so much of the time at extreme ranges, necessitating the use of supercharge ammunition, that the tubes were beginning to wear out. In reply to this request, Major General Wilhelm D. Styer (July 22, 1893 – February 26, 1975), Chief of Staff of Army Service Forces, cabled that the tubes were not immediately available and asked whether the theater could use the M1 240 millimeter howitzer for some missions then assigned to the M1 155 millimeter Gun. At the time, the American commanders in Italy were not eager for the M1 240 millimeter Howitzer. Major General John Porter Lucas (January 14, 1890 – December 24, 1949), then commander of VI Corps, was “doubtful of the value of the M1 240 Howitzer in this country.” The 5th Army Artillery officer thought that both the 240 millimeter Howitzer and the 8-Inch Gun would be “quite useful,” but that “the road network and mountains make their movement and employment extremely difficult.” Nevertheless, the theater agreed to accept 2 battalions of M1 240 millimeter Howitzers and also asked for 2 battalions of 8 Inch Howitzers, which had a range of 18,500 yards. The 4 battalions were to be used “for destruction of field fortifications and to relieve the M1 155 millimeter units of many missions which are now causing rapid destruction [of] gun tubes.” 2 battalions of M1 8 Inch Howitzers were in position on the main Italian front by November 20, 1943, and were immediately successful, especially for close support of infantry, because of their accuracy and power. The M1 240 millimeter Howitzers were delayed because the heavy tractor designed to move them was not yet available. The Ordnance Department recommended that the T2 tank recovery vehicle, with modifications, be used. In spite of the Field Artillery Board’s objections, the T2 was decided upon, and the M1 240 millimeter Howitzers were shipped before the end of 1943. Successfully moved by the T2 tank recovery vehicle, 2 batteries of M1 240 millimeter Howitzers were in position near Mignano on January 27 and began firing next day. Both battalions of 8 Inch Howitzers were in action on the Cassino front by the end of the 3rd week in February. Remarkably accurate, with a very small expenditure of ammunition the howitzers demolished important bridges behind the German lines, notably the bridge at Pontecorvo, funneling traffic from the south and west into the Liri Valley. They were extremely effective against big buildings in Cassino and other heavy masonry structures, especially when used with the concrete-piercing fuze. According to a British artillery brigadier, the fire of the 240 millimeter and 8-inch howitzer batteries was largely responsible for the ultimate reduction of the monastery at Cassino. The heavy howitzers were ideal for the main 5th Army front, which was “howitzer country,” because they could deliver a heavy weight of explosive on the reverse slopes of mountains. In operations in the high Apennines after the capture of Rome, Major General Alfred M. Gruenther (March 3, 1899 – May 30, 1983) considered the M1 240 millimeter Howitzer the most generally satisfactory artillery weapon 5th Army had. Late in March 1944 12 M1 8 Inch Howitzers and 2 M1 240 millimeter Howitzers were sent from the Cassino front to Anzio. In their 1st mission they demolished a tower in Littoria, a strong German observation point that the Germans had been using to direct fire on the port. The howitzer was good, with its split trail. The carriage is the same as that used on the M1 8 Inch (203 millimeter) Gun and requires extensive preparations to transition the gun to or from its firing position. The M35 and other tracked high-speed tractors were designed for the heavier M1 8-Inch Gun and its partner M1 240 millimeter Howitzer which was a different artillery system altogether. These were designed to be transported with gun and split trail carriage separated and mou ted on special trailers to the gun site where there were assembled using a crane. The transport of such a massive weapon was not easy (2 separated loads) and putting it in firing position could take up to 8 hours, unless special materials was available. Its main battlefield was Italy, employed both the United States Army and the United Kingdom Royal Army. Both continued to use them until the late fifties, when the ammunitions supplies ran out. Their confidence in the mountains as an obstacle to the Allied advance shattered, the Germans were also in for some surprises along the Tyrrhenian coast, where the 337th Infantry’s capture of Maranola had outflanked their positions east of Formia. Thus, the 338th Infantry, advancing astride Highway 7, was able to catch up with and eventually overtake its neighboring regiment in the mountains on the right. The 338th Infantry captured Formia against only scattered resistance on the afternoon of January 18, 1944, and continued on to the important junction of the coastal highway with the Itri-Pico road, less than a mile away. There was no opposition. Acting on Generalfeldmarschall Albert Kesselring’s (November 30, 1885 – July 16, 1960) orders to Vietinghoff, General der Panzertruppe Fridolin von Senger und Etterlin (September 4, 1891 – January 9, 1963) had already ordered a withdrawal to a line extending about 4 miles southwest from Itri to Monte Moneta. From that line, which was only a delaying position, the Germans were to fall back to a line between Fondi and Terracina, the remaining strongpoints of the Hitler Line on the 10th Army’s right flank. Only a rear guard remained at Itri and on Monte Grande. The withdrawal in the coastal corridor came none too soon, for the 88th Division’s leading regiment, the 351st Infantry, was about to cut the last escape route along Highway 7. During the afternoon and evening of the 18th the 351st Infantry’s reserve battalion arrived before Itri and the 601st and 697th Artillery Battalions, moving up from Maranola, drew within range of the Germans even as they were preparing to withdraw to their 1st delaying positions between Itri and Monte Moneta. At that point, the American infantrymen, well supported by artillery, attacked at dawn on January 19, 1944. Opposed only by a rear guard, the Americans easily occupied Monte Grande by midmorning. Cameraman 1st Lieutenant Joseph D. “Shorty” Boyle (March 6, 1916 – February 7, 2007) had been sent to England aboard the Queen Elizabeth in August 1942. He arrived in Oran on November 11, 1942, and joined the 163rd Photo Signal Company. A horseback riding instructor, Boyle didn’t have photography experience; he developed a talent for photography at Camp Roberts, Utah, and his photos appeared in “The Dispatch,” the camp newspaper. He landed at Salerno, Anzio, and Southern France. At the end of the war, he told interviewers, “Holy God, thank the Lord that the Allies won the war, because what would this world be like had the other side won?” | |
| Image Filename | wwii0634.jpg |
| Image Size | 1.02 MB |
| Image Dimensions | 2912 x 2332 |
| Photographer | Joseph D. Boyle |
| Photographer Title | United States Army Signal Corps |
| Caption Author | Written or Adapted by Jason McDonald |
| Date Photographed | January 30, 1944 |
| Location | |
| City | Mignano |
| State or Province | Campania |
| Country | Italy |
| Archive | National Archives and Records Administration |
| Record Number | NWDNS-111-SC-187126 |
| Status | Caption ©2026 MFA Productions LLC Please Do Not Duplicate or Distribute Without Permission; Image in the Public Domain |
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