The 1950s were years of profound change in the Middle East. In the realm of great power diplomacy, British hegemony gradually gave way to American ascendancy which, in turn, competed with the rapid spread of Soviet influence in the area. Within the region, the era witnessed the crystallization of a state system and, simultaneously, the growth of ideological movements dedicated to the unification of those states on national or religious bases. Internally, Middle Eastern governments sought new of opposition groups. These transformations, together with the dislocations of decolonization, the persistence of regional rivalries, and the introduction of new technologies, caused chronic instability throughout the Middle East, and in the winter of 1955–1956, combined to produce Britain's crisis in Jordan.