 Foulkes had served under Simonds in World War Two, and the two generals were well known for their acrimonious relations as Simonds always took the view that Foulkes was incompetent.Simonds successfully argued that for historical reasons and because of doubts about the combat efficiency of the U.S Army that the Canadians should serve as part of the British Army of the Rhine in northern Germany.The way in which the North Koreans had driven the Americans back to the Pusan perimeter in the summer of 1950 followed by the Chinese victory along the Yalu in November 1950 had "shocked" Canadian decision-makers and created major doubts about the quality of the U.S. Army.