Since the thirteenth century, the kingdom of Castile has brought into being an important commercial development relating to wool (thanks to the well-known sea route Carrera a Flandes), connected the Cantab rian, Atlantic and the North Seas, and established a close link between Burgos and Bruges. By the end of the fifteenth century, even as the Castilian maritime traffic was favoured by the the Castilian mercantile associations and the creation of the consulate of Burgos, it yet showed the vicissitudes induced by political and economic conjunctures. This implied the decay of wool trade and the above-mentioned cities. Medieval precedents nevertheless exercised a strong presence in the Spanish colonial trade in America or Carrera de Indias.