During the Korean War (1950–1953) the Norwegian government sent a mobile army surgical hospital (MASH) to support the efforts of the United Nations (UN) Army. From the first, its status was ambiguous. The US-led military medical services believed that the “Norwegian Mobile Army Surgical Hospital” (NORMASH) was no different from any other MASH; but both its originators and its staff regarded it as a vehicle for humanitarian aid. Members of the hospital soon recognized that their status in the war zone was primarily that of a military field hospital. Yet they insisted on providing essential medical care to the local civilian population as well as trauma care to UN soldiers and prisoners of war. The ambiguities that arose from the dual mission of NORMASH are explored in this article, which pays particular attention to the experiences of nurses, as expressed in three types of source: their contemporary letters to their Matron-in-Chief; a report written by one nurse shortly after the war; and a series of oral history interviews conducted approximately 60 years later. The article concludes that the nurses of NORMASH experienced no real role-conflict. They viewed it as natural that they should offer their services to both military and civilian casualties according to need, and they experienced a sense of satisfaction from their work with both types of patient. Ultimately, the experience of Norwegian nurses in Korea illustrates the powerful sense of personal agency that could be experienced by nurses in forward field hospitals, where political decision-making did not impinge too forcefully on their clinical and ethical judgment as clinicians.