When World War II started in Europe in 1939, he worked as a war correspondent for the "Chicago Daily News" and the "New York Post". He happened to be in Oslo on April 9, 1940 and therefore witnessed the German invasion, as well as the general confusion within the Norwegian forces, administration, and Allied Expeditionary Forces. Stowe "revealed the collaboration of Norwegian Vidkun Quisling in helping the Nazis seize Oslo without a shot." In 1942 Stowe as a war correspondent visited Moscow and traveled to the front lines of the still retreating troops of USSR. His travel companion and guide was Ilya Ehrenburg, a Russian-Jewish-Soviet war journalist. Stowe's book "They Shall Not Sleep" gives a rare insider view of an American journalist on the Soviet Army, and the events of the war from the Soviet side of the front.