Prior to the era of explicit racial ideologies, immigration had never emerged as a serious problem in international relations. After this, however, a growing public pressure to maintain what was called "racial purity" against "inferior beings of colour" led to the creation of exclusion laws designed to erect a "colour bar" and thereby restrict non-white immigration. Central and South American states all protested against the so-called "Yellow Peril" and imposed laws to limit immigrants from Japan, China and other Asiatic countries. South Africa created similar laws of racial exclusion which, in turn, served as the basis for other discriminatory statutes designed to establish control by a white-minority regime.