In 1545, miners struck silver in what would become one of the richest veins in the entire New World, the near legendary Cerro Rico of Potosí, in the Andean highlands of Peru. This strike prompted swift action on the part of royal authorities. They sought to rearrange existing land and labor systems and to establish new ones to meet the spiraling economic demands. Simultaneously they had to cope with a dramatic, unprecedented drop in the indigenous population which hitherto had supplied needed labor. The crown turned elsewhere, and authorized the exploitation of another, far more distant group of people. Slaves from Africa became an additional, ongoing source of much needed labor in the Andes.