By 1400 the long running conflict between the Order of Teutonic Knights and Poland and Lithuania was coming to a head, partly as a result of the Order's meddling in the internal politics of its neighbours. In June 1410 King Wladislaw Jagiello of Poland invaded the Order's territory with a powerful allied army including all the enemies of the Teutonic Knights — Poles, Lithuanians, Russians, Bohemians, Hungarians, Tartars and Cossacks. This book recounts how, when the armies clashed on the wooded, rolling hills near the small village of Tannenberg, the Teutonic Knights suffered a disastrous defeat from which their Order never recovered.