[7] MK's origins date to 1905, when Harry Morrison, Chairman and President[9] met Morris Knudsen[10] while working on the construction of the New York Canal (Boise Project) in southwestern Idaho.

Morrison was a 20-year-old concrete superintendent for the Reclamation Service; Knudsen was a forty-something Nebraska farmer (and Danish immigrant) with a team of horses and a fresno scraper.

MK earned some revenue in 1914, when they constructed the Three Mile Falls Diversion Dam, south of Umatilla, Oregon.

Japanese forces captured 1,200 workers, including many MK employees, stationed on Midway and Wake Islands in late 1941.

[21] In the late 1960s and early 1970s, MK was involved in the construction of the Hamersley & Robe River and Mount Newman railways in the Pilbara region of Western Australia.

[22][23][24] From 1962 to 1972, MK managed a joint venture to serve the U.S. military as civilian contractors for infrastructure in the Vietnam War;[25] in 1971, they constructed 384 of the infamous "tiger cage" cells of Côn Sơn Prison.

[26][27] The group was called RMK-BRJ and included Raymond International, Brown & Root, and JA Jones Construction Company.

[28] MK also entered the passenger railcar rebuilding market in the 1980s, initially located at the former Erie Railroad shop in Hornell, New York.

[citation needed] MK later expanded into building new cars, taking over the former Pullman Company factory in Chicago in 1992.

[48] By the 1990s, Morrison–Knudsen had been led into some risky non-core areas by Boise native William Agee, who became CEO in 1988 and was ousted by the board of directors in February 1995.

In 1999, MK acquired the government-services operations of Westinghouse Electric Company,[58] becoming a science and technology services leader.

[60] Issues with the Raytheon acquisition[62] caused WGI to declare bankruptcy in 2001[63] – virtually eliminating all shareholder value, but later successfully exited it.