Since Napa Valley winemakers couldn't simply make a wine with the Bordeaux name on the label, they did the next best thing: They imported Bordeaux grapes (including Cabernet Sauvignon and Merlot) and learned French winemaking techniques. You have to remember that back then, most California wines were sold in jugs (or worse, tanks!) and aged in large redwood vatsa very different scene from today's production process.