The medieval workhorse that everyone despised and no one could do without. Gouais Blanc — the German Heunisch — was the high-yielding, tart white of the peasant vineyard, so ordinary that lords repeatedly tried to ban it in favour of nobler grapes. Yet it grew everywhere beside Pinot, and that accident of proximity made it one of the most important parents in the history of wine.
DNA has shown that Gouais Blanc crossed with Pinot gave, among others, Chardonnay, Gamay, Aligoté and Melon de Bourgogne, and that its wider progeny includes Riesling and Furmint — well over a dozen of Europe's grapes descend from this scorned vine. Nearly extinct in the vineyard today and kept alive chiefly in collections, it is the humble root of a startling share of the fine-wine map.