The Jesuits were instrumental in the colonization of the indigenous peoples of the eastern lowlands of what are today the departments of Santa Cruz and Beni. The missions they established at the end of the seventeenth century through the mid-eighteenth were modeled on the ideal cities proposed by sixteenth-century humanist philosophers and were influenced by both church architecture and local building materials and styles. In 1767, the Spanish Crown expelled the Jesuits from the missions and the Americas, as part of a consolidation of secular over religious power. Alcide d’Orbigny, the French scientific traveler and natural historian (see part VI), visited the eastern lowlands in the early years after independence, once the erstwhile Spanish colonies had been opened up to foreign travelers and trade. His drawings lay out the mission settlements in Concepción (Moxos region) and San José (Chiquitos region), based on information provided by the descendants of the colonial residents. The missions were important economic and demographic centers, and the drawings depict the religious, manufacturing, and residential core surrounded by plantation fields and communal gardens. Traces of the colonial mission culture remain evident in the mid-twentieth-century imagery of the German photographer Hans Ertl.