In the nineteenth century, the attraction of the sea and its landscapes occupied the collective imagination and it then became a particularly interesting theme for professional historians and learned people. From the middle of the thirteenth century, La Rochelle was the principal outlet for the whole of central-western France, which created intensive commercial relations between the port and its hinterland. The great fleets calling at La Rochelle for wine and salt increased the opportunities for Castilian traders to find buyers for their wool, which was to be processed by the North European textile industries. In any case, grain was the dominant product of the medieval subsistence economy, while the region around La Rochelle produced nearly exclusively wine. La Rochelle effectively concentrated most of the wine trade, as it was also home to the mint, scores of moneychangers and notaries, and its commercial and financial networks.