The Difficult alliance. Military cooperation between the ruthenian king Daniel and the Piasts of Mazovia

Abstract The article presents the military cooperation between the King of Galician-Volhynian Ruthenia, Daniel Romanowicz, and the Dukes of Mazovia, Konrad and his son Siemowit. The alliance, based as a counterweight for the cooperation between the King of Hungary and the Piast princes of Lesser Poland, who were trying to conquer Ruthenia and dominate all Piast principalities in then fragmented Poland. It lasted for several decades from the 1220’s to the 1260’s and was primarly aimed at mutual protection against the invasions of the pagan Yotvingians and supporting each other in armed conflicts. The text contains an analysis of war expeditions, tactics and ways of support that were given by both sides of the allianace. It is a new point of view on this aspect of political strategy of both sides that in some ways defined the regional situation. Ruthenians granted masovian Piasts some mobile and political uncommited support in fight with their relatives in Poland, and also secured their border with the Yotvingians. On the other hand, masovian knights were an additional strike force in ruthenian plundering expeditions to Yotvingia. The research was based on the analysis of preserved historical sources and scientific literature using historical methodology.