The aim of this text is to map a body of practices and institutions related to safeguarding policies in Portugal and Brazil through extensive bibliographic and legal research. This research includes the issuing of the first Portuguese law directly regulating the preservation of Cultural Heritage in August 1721, the reconstruction of Lisbon, and the establishment of academies and museums. The growth of a shared scientific culture gained particular importance in Brazil during the period when the Portuguese Court resided in Rio de Janeiro, on the brink of independence in 1822. The text sheds light on a variety of sources, providing a foundation for new narratives in Portuguese-Brazilian heritage history.