Francisco de Toledo, "one of the great administrators of human times", established the Inquisition in the viceroyalty and promulgated laws that applied to Indians and Spanish alike, breaking the power of the encomenderos and reducing the old system of "mita" (the Incan system of mandatory labor tribute). He improved the defensibility of the viceroyalty with fortifications, bridges, and "la Armada del Mar del Sur" (the Southern Fleet) against pirates. He ended the indigenous Neo-Inca State in Vilcabamba, executing the Inca Túpac Amaru, and promoted economic development from the commercial monopoly and mineral extraction, mainly from silver mines in Potosí.