https://www.gunsandammo.com/editoria...irearms/386310
The War Effort
In April 1915, with World War I just six months old, Marlin was approached on a contract for 100,000 7x57 Mauser rifles. Marlin President Mahlon Marlin demurred, believing such an order was too large to deliver in a timely manner. But Marlin would not stay out of the war. In December 1915, the Marlin Fire Arms Company was acquired by a syndicate and the Marlin Arms Corporation was formed, with the name soon changed to Marlin-*Rockwell. Marlin was headed by Albert Rockwell from 1915 to 1920.
Part of the arrangement was an initial contract to produce 12,000 1914 Colt machine guns. The so-called “potato digger” was significantly improved into the 1917 Marlin-*Rockwell machine gun. Marlin became one of the largest producers of machine guns, making both Colt and Browning 1918 guns for aircraft use. In 1918, they received a contract for 20,000 Browning Automatic Rifles (BAR), delivering 16,000 by the end of the war. During World War I, Marlin-*Rockwell produced more than 60,000 machine guns and Browning Automatic Rifles (BAR).
During World War II, virtually all manufacturing facilities focused on the war effort. Marlin manufactured about 15,000 United Defense M42 sub-machine guns, but the majority of the wartime manufacture was parts. Hundreds of thousands of stocks, handguards, and barrels for the M1 carbine, barrel assemblies for the Garand, and various parts for both aircraft and small arms were made. During the Korean War, Marlin tooled up again, producing Garand and carbine parts, and thousands of barrels for the M3 sub-machine gun. Many World War II parts are not marked as made by Marlin, but carbine barrels and all barrels made during the Korean era are stamped “MARLIN”.
https://www.forgottenweapons.com/at-...lin-ud-42-smg/
https://www.forgottenweapons.com/mar...t-machine-gun/