River trade was of great importance in the development of vineyards. The Germanic countries benefited from the navigability of the Rhine and the Danube so they could export their production. Charlemagne contributed to this growth by enacting his Capitulare de villis which included a set of rules on the cultivation of the vine in all areas. It was an era of great development of the culture of white wine in Germany and Austria. The Central European vineyards reached 100,000 hectares, which was three and a half times the area in the 1990s. From the 13th century traders distinguished vinum hunicum (wine of the Huns), which was drunk by the people, from vinum francium (Wine of the Franks) which was the wine for the wealthy aristocracy. There was recognition of varieties of Riesling and Sylvaner from the late Middle Ages. Part of European trade was by sea along the Atlantic coast. The English, then the Dutch and Scandinavians from their demand for wine, created a craze for planting between Bordeaux and La Rochelle. Little dry white wine was produced for export from La Rochelle while Bordeaux exported mainly wines from the hinterland received via the Garonne. When wine production was introduced on the banks of the Charente in the 17th century, Charente white wines were introduced as cognac. At the same time, the dry white wine popular with the Dutch was produced to the north, around the port of Nantes from the current areas of Muscadet AOC and Gros-plant AOVDQS in the Loire Valley. Vineyards in the Loire Valley and the South-west had their sales network thanks to the navigability of the Loire and the Garonne. In the Mediterranean Basin the Crusades greatly enriched both rival republics of Venice and Genoa. To supply the troops of the rich Frankish lords these republics provided them with wine from Greece. The port of Monemvasia, which exported a large amount of white wine, gave its name to the variety Malvasia. The Crusaders also discovered Muscat wine. Once back home, the rulers and wealthy aristocrats looked to buy the sweet wines they enjoyed in the East. They came from grapes that dominated the vineyards of Languedoc-Roussillon and Spain. Trade in these wines was facilitated by their high alcohol content which ensured preservation during the long journey to Northern Europe. Modern era In 1453 the Ottoman Empire took Constantinople and the situation of the Venetians and