PhD in American History from the Universidad Complutense de Madrid (1989) and scientific researcher at the Consejo Superior de Investigaciones Científicas (1999), assigned to the Escuela de Estudios Hispano-Americanos, of which he has been director for two periods. He completed his training at the Instituto de Investigaciones Histórica (UNAM) and at Southern Methodist University (Dallas). He was awarded the Conacyt Chair at the Universidad Autónoma de Zacatecas. He specialises in European Expansion in America and the Pacific, as well as in the construction of Spanish Americanism (19th-20th centuries). In addition to the reference book La aventura de lo imposible. Expediciones marítimas españolas (Madrid, Museo Naval, 2000), it is worth mentioning Poblar la inmensidad. Sociedades, conflictividad y representación en los márgenes del Imperio Hispánico (siglos XV-XIX) (Madrid, Ediciones Rubeo-CSIC, 2010); La Nao de China, 1565-1815. Navegación, comercio e intercambios culturales (Seville, University of Seville, 2014), Un océano de seda y plata: el universo económico del Galeón de Manila (Madrid, CSIC, 2013), in collaboration with Carlos Martínez Shaw, and Conocer el Pacífico. Exploraciones, imágenes y formación de sociedades oceánicas (Seville, Editorial Universidad de Sevilla, 2015), coordinated with Carmen Mena and Emilio José Luque Azcona. For several years he has been the editorial secretary and director of the Anuario de Estudios Americanos.