For the first time all about the army of Charles XII! The Great Northern War of 1700-1721. became a turning point in the history of many countries and peoples of Northern and Eastern Europe. For Russia, its result was the return of lands seized by Sweden in the past, securing access to the Baltic Sea and becoming a great world power. In addition, the military art of the Russian regular army was due to the fact that from the very beginning it had to resist the best European army of that time - the Swedish army of King Charles XII, one of the largest commanders of the 18th century, whose state was the second largest in Europe, second only to Russia itself. However, in domestic literature, military art and the organization of the Swedish army of its golden age received practically no coverage. The book of Doctor of Historical Sciences A.V. Bespalova in all details shows the development of the military art of the army of Charles XII and covers little-studied episodes of its military path in Poland, the Baltic states, Ukraine and Russia. The reader learns about the Swedish army's command system and its top command staff; development of the system of acquisition, supply and strengthening of discipline; strategy and tactics of the Swedish king; his guard; artillery of Sweden in the Northern War; uniforms and banners of Charles XII's army.