Between 1534 and 1566, Charles V and Philip II laid the foundations of the early modern monetary system. Consisting of gold escudos, silver reales and billon maravedís, it was initially intended only for the Crown of Castile, as the Spanish monarchy did not have a unified system.
However, the growing importance of American viceroyalties, where Castilian coins became the norm, and international success eventually made it one of the most widespread and enduring currency systems. Established throughout the Iberian Peninsula from the 18th century, it remained in use until the mid-1800s.
In keeping with the new global economy, escudos, doblones or doubloons (two and four-escudo pieces) and onzas (eight-escudo pieces) were made in both the Americas and mainland Spain, providing high-value currency for bankers, merchants and the state itself, whose expansive ambitions and constant military campaigns required vast amounts of money.
The escudo underwent many major technological and design changes in its long life. The most important was mechanisation, which began in 1582 with the installation of the Real Ingenio in Segovia, an innovative hydraulic coin-minting system for which an advanced industrial complex, the first of its kind in Europe, was designed by the architect Juan de Herrera.