His "Teutonic Knights" returned to Poland's history, describing the Battle of Grunwald (1410), a Polish-Lithuanian victory over the Teutonic Knights in the Polish-Lithuanian-Teutonic War. Both in German and Polish culture the Teutonic Knights were incorrectly viewed as precursors to modern Germans while the Polish-Lithuanian union was regarded as a model for a future independent Polish state. These assumptions tied in well with the contemporary political context of ongoing Germanization efforts in German Poland. So, the book quickly became another Sienkiewicz bestseller in Poland, and was received by critics better than his Trilogy had been; it was also applauded by the Polish right-wing, anti-German National Democracy political movement, and became part of the Polish school curriculum after Poland regained independence in 1918.