The team project focused on European-indigenous cross-cultural transfer studied through sources directly related to indigenous nobility of Central Mexico (Nahua elites) and Peru (Quechua elites). Archival searches realized by team members in Mexico, Peru and Spain made it possible to discover and analyse a large body of previously unknown and/or unstudied documents in Nahuatl and Spanish. This research has been also enriched by complementary analyses of indigenous pictorial sources. Searches carried out in the Archivo General de la Nación, Archivo Histórico del Arzobispado de México in Mexico, municipal and parish archives in the state of Tlaxcala, Archivo General de Indias in Seville as well as Archivo General de la Nación in Lima and Archivo Arzobispal de Lima in Peru made it possible to explore many other documents in Nahuatl and Spanish, directly linked to high-ranking Aztec and Andean aristocracy, as well as to representatives of lower nobility. The corpus contains wills, legal documents, land-sale documents, accounts, letters, and petitions to the king of Spain (for specific privileges such as land, coats of arms, etc.). The petitions especially were generated and supported by a vision of native nobility as inheritors of a dual Christian-Aztec tradition. This comparative analysis of documents originating in two very important areas of pre-Columbian civilization, and, at the same time, key zones of Spanish colonization, enabled us to perceive and comprehend the whole spectrum of phenomena and processes linked to the survival of indigenous nobility in dialogue with both local and foreign traditions. Hitherto unstudied wills from the Nahua world and from Peru have provided important information on the “middle class”, which actively participated in the socio-political, religious and economic life of the colonial period, often relying on the same mechanisms and sources of legitimacy for their position as the high aristocracy. The selection of sources and research methods made it possible to utilize a microhistorical perspective while at the same time interpreting the phenomena under study in a broader macrohistorical context.