New coins appeared in the Christian kingdoms beginning in the 13th century, as their societies and domestic economies diversified and the needs of the state and international trade increased.
While the Crown of Aragon looked to Italy when choosing a system for its gold currency, that of Castile maintained its historical ties to Al-Andalus: until the late 15th century it continued to use the Islamic weight standard, albeit with completely different images.
The Castilian name for the Almohad and Nasrid dinar was “dobla”, which also became the gold coin of the Crown of Castile. The oldest known doblas were minted by Alfonso X the Wise (1252–1284), whose expansive reign required a steady supply of hard currency. The coin’s two sides featured the emblems of Castile and Leon and Alfonso’s titles as monarch of both kingdoms, which were definitely united in 1230 by his father, Ferdinand III.
The dobla endured for more than two centuries, with variations in the design that are reflected in the names it received. There were doblas de cabeza or “head doblas” (with the king’s bust), doblas de la banda (after the sash-crossed crest of the Order of the Band), doble enriques de la silla or “double Henrys of the chair” (featuring Henry IV enthroned) and castellanos (after the castle).