The Thirty Years' War exerted a great influence over German territorial principalities of the Holy Roman Empire during the 17th century. This is particularly true for development of the German national idea. The Germans met a lot of strangers, such as Spaniards, Danes, Swedes, who came with foreign armies during the War. French contact was the most important. The French invasion began only at the end of the War. Nevertheless, German social and political journalism accused France of warmongering. Since 1635 a hostile image of Frenchman has begun to appear on the pages of German reading materials. He destroyed German traditions, culture and moral values. At a time when France occupied territorials in South, Central and Eastern Germany typical stereotypes of German national thought were born for the next centuries. It was the result of «us versus them» concept.