1) Dutch surname 
Owner family of the Diefenhardt'sches Weingut winery (Rheingau); see there Diefenhardt's vineyard The winery is located in the municipality of Martinsthal in the German Rheingau wine region. It looks back on several hundred years of history and tradition. The cellars still in use today date back to the 17th century. In 1917 Jacob Diefenhardt a...