Colt was the primary manufacturer during WW1, turning out approx. 700,000 pistols. The government-owned Springfield Armory made 25,000 and Remington-UMC made 20,000 pistols. 100 were made by North American Arms but were never accepted by the military.
WW2- Colt made 600,000 pistols, but wasn't the main producer. 800,000 were made by Remington Rand (a typewriter company), 300,000 by Ithaca Gun Co, 50,000 by Union Switch & Signal (a railroad equipment co.), and of course 500 made by Singer Sewing Machine Co.
The new commercial Springfield Armory was incorporated in 1974. Kimber was also in business during the 1970's, but didn't make 1911's until 1996.