Texas and the Old World
Here is a simplified illustration of Texas in relation to the Old World. It can help to realize that France alone has multiple growing regions, each with distinct terroir and choice of grape varietals. Texas is larger than France, and one can begin to see why Texas grape growers are continuing to experiment with varietals that differ from the established American wine regions.
Italy is one of the world's top wine-producing countries, and it is home to a wide variety of grape varieties. According to the Italian National Institute of Statistics, there are around 400 different grape varieties grown in Italy commercially.
Portugal is also known for a wide variety of grape varieties, though not as many as Italy. Estimates suggest that there are around 250 grape varieties grown in Portugal.
According to the Spanish Ministry of Agriculture, Fisheries, Food and Environment, there are more than 400 different grape varieties grown in Spain.
In Southern France the estimates suggest that there are around 80 to 100 different grape varieties grown in the region.