In the 7th century the history of viticulture on Lake Constance began with the Christianization of the Alemanni by the Franks. The monasteries on Lake Constance formed the centers of viticulture in the early Middle Ages, primarily due to their great need for communion wine.
Already at that time, the village of Hagnau was in demand because of its central location on Lake Constance and especially because of the fertile soil. So, it is not surprising that Hagnau kept getting different ownership. First mentioned in the year 1010, the village was initially owned by the aristocrats of Ittendorf. Then the village changed over to Weingarten Abbey and afterwards came into the possession of the free imperial city of Überlingen for more than 200 years.
The Hagnau winegrower association was founded on October 20, 1881. It is the first wine cooperative in the region of Baden / South of Germany.
The writer and civil rights activist Dr. Heinrich Hansjakob, pastor in Hagnau since 1869, recognized the economic plight of the Hagnau citizens and tried to counteract it by uniting the winegrowers. In October 1881, when the wine price dropped to 15 pennies per liter and the winegrowers were forced to sell at this ridiculous price, Heinrich Hansjakob called on the citizens of Hagnau to found a winegrower association. This is how the first Baden winegrower cooperative was founded in Hagnau at Lake Constance on October 20, 1881. The work of the great pastor Dr. Heinrich Hansjakob bore good fruit.