The Knights Templar, which existed from the 12th to 14th centuries, have acquired a mysterious and conspiratorial reputation in modern pop culture. The Da Vinci Code by Dan Brown is but one popular book that has dealt with the Knights. Yet the real Knights were often more ordinary than commonly depicted.
To financially support their military endeavors, the Knights Templar engaged in various businesses, including wine making. A significant agricultural area for the Knights was Catalonia in Spain. Renaissance Magazine (issue #67) just published an article "Days of Wine and Olive Oil" written by Paula Stiles. This interesting, albeit brief, article discusses the role of the Knights in wine making in Catalonia.
The Knights drank wine every day and their wine consumption was governed by certain regulations. The wine they drank had to be diluted, and they also had to share a glass with another person. This all seemed directed at preventing the Knights from getting drunk. They may have used the traditional porron. It is also likely they drank wines made with Spanish grapes like Tempranillo, Paralleda and Garnacha.
Check out the article, or maybe do research elsewhere to learn more about the Templars and their wine making.