King Charles, an experienced former general from the Thirty Years' War, saw the war as an opportunity to put an end to the Polish King's claim to the Swedish throne and to gain additional territories which would enable him to control the Baltic Sea. The book presents new research on a war previously seldom described in English.

Professor Michael Fredholm von Essen is an historian and former military analyst who has published extensively on the history, defence strategies, security policies, and energy sector developments of Eurasia. He currently is the Head of Research and Development at IRI, an independent research institute. Educated at Uppsala, Stockholm, and Lund Universities, Michael Fredholm von Essen has lectured, including during conferences and as visiting professor, at numerous institutions and universities around the world. He is the author of a large number of books, articles, and academic papers, including Muscovy's Soldiers: The Emergence of the Russian Army, 1462-1689 (Helion, 2018); Charles XI's War: The Scanian War between Sweden and Denmark, 1675-1679 (Helion, 2018); Transnational Organized Crime and Jihadist Terrorism: Russian-Speaking Networks in Western Europe (Routledge, 2017); Understanding Lone Actor Terrorism: Past Experience, Future Outlook, and Response Strategies (Routledge, 2016); Afghanistan Beyond the Fog of War: Persistent Failure of a Rentier State (NIAS, 2018); Eight Banners and Green Flag: The Army of the Manchu Empire and Qing China, 1600-1850 (Pike and Shot Society, 2009); and a large number of articles on early modern warfare in the Arquebusier, the journal of the Pike and Shot Society.