The M198 is a U.S.-designed 155 mm towed howitzer developed at Rock Island Arsenal to replace older M114-series guns. Its split-trail carriage, nine-person crew, air-transportable layout, and 22-30 km range made it a standard U.S. Army and Marine Corps fire-support weapon before the lighter M777 replaced it in U.S. service. Direct conflict sourcing now traces M198 fielding from Desert Storm through U.S. use in Afghanistan and Iraq, Islamic State capture and cross-border use in Iraq and Syria, Iraq-aligned militia firing, and coalition-backed Iraqi Army live-fire training.
Battery F, 2nd Battalion, 12th Marines operated an M198 during the Battle of Al Khafji in Operation Desert Storm; a Marine Corps account identifies that howitzer as firing the opening shot in support of Marine and coalition forces near the Saudi border.
Role detailsU.S. forces fielded M198 howitzers in Afghanistan: DVIDS documents a January 2005 show-of-force mission by Fox Battery at FOB Salerno and an October 2009 firing at FOB Mehtar Lam to support forward maneuvering elements.
Role detailsU.S. Marine Corps M198s were documented firing around Fallujah in 2004, including supporting and defensive fires for Camp Fallujah and fire on an insurgent position during Operation al Fajr.
Role detailsIslamic State forces captured Iraqi M198 155 mm howitzers during the 2014 offensive and were later reported on video firing an M198; Iraq-aligned Hezbollah Brigades fighters were separately reported firing U.S.-made M198 towed artillery in support of the Tikrit operation in 2015, while coalition imagery documents Iraqi Army M198 live-fire training at Besmaya in 2018.
Islamic State forces moved U.S.-made M198 howitzers captured in Iraq into the Syrian theater; Bellingcat reported Islamic State UAV spotting for M198 shelling around Kweres airbase, and Oryx listed three 155 mm M198 howitzers among Islamic State equipment documented inside Syria.
The M198 was built around a useful compromise: heavier and longer-ranged than light infantry mortars, but still movable by truck, parachute delivery, and heavy-lift helicopter when the tactical problem justified it.
A nine-person crew served the gun, with a listed maximum rate of four rounds per minute, a sustained rate of two rounds per minute, and about six minutes into action in FAS reference data.
Sources: M198 155mm Howitzer; FAS M198 Towed Howitzer.
Published specifications place conventional projectile range around 22.4 km and rocket-assisted range around 30 km.
Sources: M198 155mm Howitzer; PEO Ammunition Portfolio Book 2017.
Official and Marine Corps sources emphasize parachute or aircraft delivery, CH-47 and CH-53E lift, and rapid helicopter insertion into temporary firing positions.
Sources: RIA Self-Guided Tour: M198 155MM Towed Howitzer; FAS M198 Towed Howitzer; Fire mission!
The M198 fires separate-loading 155 mm ammunition; open Army and specialist references tie the gun to conventional HE, rocket-assisted, and guided projectile families already represented in the catalog.
| Ammunition | Ammunition type | Firing evidence |
|---|---|---|
 | 155 mm high-explosive projectile | The 2017 Army ammunition portfolio lists M198 series howitzers as a weapon system for the M107 projectile. Sources: PEO Ammunition Portfolio Book 2017 |
 | 155 mm high-explosive projectile | GICHD's Ukraine explosive-ordnance guide lists the M795 projectile as usable with M198 155 mm howitzers. |
 | 155 mm rocket-assisted projectile | Army ammunition references use M198-class firing data for M549A1 rocket-assisted projectile range, tying the round to M198-series howitzers. Sources: M549A1 Rocket Assisted Projectile, PEO Ammunition Portfolio Book 2017 |
 | 155 mm laser-guided projectile | Ultra Defense lists Copperhead among the M198's projectile options, and a public-domain file identifies an M712 Copperhead fired from a modified M198 howitzer. Sources: M198 155mm Howitzer, File:M712 Copperhead is fired out of a M198 howitzer.JPEG |
 | 155 mm GPS-guided projectile | Raytheon said the U.S. Army Excalibur Program Office determined Excalibur Ib fully compatible with the M198 howitzer when used with the Modular Artillery Charge System. Sources: Raytheon's Excalibur Ib Compatible with M198 howitzer |
Mobility was a defining M198 design feature: official Army and Air Force sources describe helicopter sling-load and parachute or aircraft delivery options for the howitzer.
| Carrier | Carrier type | Carriage evidence |
|---|---|---|
 | Heavy-lift transport helicopter | The Army's Rock Island Arsenal tour page says the M198 can be transported by CH-47 helicopter, while Air Force reporting documents an M198 air-drop to a remote Army unit in Afghanistan. Sources: RIA Self-Guided Tour: M198 155MM Towed Howitzer, Total-force team airdrops 10-ton artillery load |
The M198 sits between two better-known U.S. towed-artillery generations: it replaced the World War II-era M114 family in U.S. service, then was itself replaced by the lighter M777.
M114 155 mm Howitzer was the predecessor the M198 program was built to replace, with longer range and faster movement cited as M198 improvements.
Sources: RIA Self-Guided Tour: M198 155MM Towed Howitzer; FAS M198 Towed Howitzer.
M777 replaced the M198 in U.S. Army and Marine Corps service while retaining the 155 mm towed-artillery role in a much lighter weapon.
Source: RIA Self-Guided Tour: M198 155MM Towed Howitzer.
Army reporting identifies RIA-JMTC as original equipment manufacturer for M198 and M119 howitzer systems, while this record keeps the historical builder facet on Rock Island Arsenal.
Source: RIA-JMTC signs agreement with Mandus Group.
Rock Island Arsenal says M198 development began in 1968 as a replacement for the older M114A2 155 mm howitzer.
Sources: RIA Self-Guided Tour: M198 155MM Towed Howitzer
Primary design and development work took place at Rock Island Arsenal's Rodman Laboratory from 1973 through 1977.
Sources: RIA Self-Guided Tour: M198 155MM Towed Howitzer
Ultra Defense states that the M198 went into full production in 1978 after prototype and firing-test work at Rock Island Arsenal.
Sources: M198 155mm Howitzer
Ultra Defense identifies 1979 as the M198's service-entry year for the U.S. Army and Marine Corps.
Sources: M198 155mm Howitzer
Marine Corps Logistics Base Barstow says an M198 nicknamed Damn Yankee fired the opening shot in support of Marine and coalition forces near the Saudi border during Operation Desert Storm.
Sources: Historic Howitzer at Barstow Destined for National Museum
A Defense Department photo caption documents Marines firing an M198 to provide supporting and defensive fire for Camp Fallujah, Iraq.
Sources: U.S. Marines fire an M198 Medium Howitzer
DVIDS describes Fox Battery firing an M198 155 mm howitzer during a show-of-force exercise at Forward Operating Base Salerno, Afghanistan.
Sources: Artillery Battery Shows Force in Afghanistan
Air Force reporting says a Bagram Air Field team air-dropped an M198 artillery piece to a remote Army unit in eastern Afghanistan.
Sources: Total-force team airdrops 10-ton artillery load
FDD's Long War Journal reported that Hezbollah Brigades released video of its fighters firing U.S.-made M198 towed artillery pieces in support of the Tikrit operation.
Sources: Shiite militias, Iraqi troops enter central Tikrit
Bellingcat reported Islamic State UAV spotting for U.S.-made M198 howitzers captured in Iraq and used to shell Kweres airbase and its surroundings in Syria.
Sources: Battlefront Syria: Kweres airbase
Raytheon said the U.S. Army Excalibur Program Office determined Excalibur Ib fully compatible with the M198 when used with the Modular Artillery Charge System.
Sources: Raytheon's Excalibur Ib Compatible with M198 howitzer
DVIDS imagery documents French forces training Iraqi Army soldiers through a live-fire exercise with an M198 155 mm howitzer at the Besmaya Range Complex during Operation Inherent Resolve.
Sources: Iraqi Army M198 with Task Force Monsabert and Wagram, Image 1
