Techniques of wetland rice agriculture became the basis of prosperity and cultural development throughout East Asia; illiteracy was dispelled by the spread of Chinese writing; Buddhism became the principal religion throughout the area; and Confucianism deeply influenced social and political institutions and eventually became the official state cult in all three countries. Indications of a shared culture are readily apparent as well in the literature, art and architecture of the three countries. The structure and appearance of public buildings, landscape painting, Buddhist sculpture, ceramic ware, and poetry in the pre-modern era is immediately recognizable as variations on common themes and techniques.