Data on musical compositions in six countries show the effect that varying conditions of a war period can have on the construction of music. Prior to World War II, pieces mitten in these nations display similar characteristics when measured across a set of musical properties. However, the outbreak of battle precipitates a deviation in this pattern. Works created in areas exposed to a high degree of social disruption exhibit change on several of the dimensions examined here; compositions written in regions that were not subjected to such disorganization show little or no change. Sociological implications are discussed.