Surrounded on all sides by Slavic and Baltic peoples and far from the cultural centers of the early Middle Ages, Poland appears in history only towards the middle of the century. X. But it immediately appears as the largest among the Slavic state units, headed by a prince – Mieszko I – strong inside and capable of conducting, albeit with some uncertainty and varying fortunes, its own foreign policy. The rapid affirmation must therefore be preceded by a period of state organization; and since nothing authorizes us to attribute credit to foreign elements – the hypothesis of a Norman incursion no longer finds credence in Polish historiography – it must be deduced that the long isolation, harmful from a cultural point of view, has allowed the Polish lands to unify and consolidate politically with their own forces. Probably up to the middle of the century. IX the Piasti dynasty, assuming power over the Polani tribe (region of Gniezno and Poznań), proceeded to the gradual subjugation of the other Polish tribes: the Silesians, Masovians, Vistolans (who, in the territory of the future Lesser Poland, had established a principality in the second half of the 9th century) and finally, but only at the end of the 9th century. X, of the Pomerans. The military organization of the lands under their dominion must also have been the work of the Piasti prior to Mieszko; a large company of warriors (they had established a principality in the second half of the century. IX) and finally, but only at the end of the century. X, of the Pomerans. The military organization of the lands under their dominion must also have been the work of the Piasti prior to Mieszko; a large company of warriors (they had established a principality in the second half of the century. IX) and finally, but only at the end of the century. X, of the Pomerans. The military organization of the lands under their dominion must also have been the work of the Piasti prior to Mieszko; a large company of warriors (dru ż yna), composed of natives and foreigners, served exclusively to their orders, also emancipating them from the power of families (rody), whose leaders, together with the warriors, would later form the first nucleus of the nobility. Starting in 963, when he was defeated by the German adventurer Wichmann, Mieszko I is in an almost continuous struggle with the German margraves, over whom he tries to ensure the friendship and protection of the emperor. What is at stake is the dominance over the western area of the territory occupied by the Elban Slavs; the result is an undoubted containment of the tenacious German expansion, but also the recognition, by Mieszko, of the sovereignty of Otto I and, after an interruption of about fifteen years, of Otto III. At the same time Mieszko extends his power longum mare, managing to subdue the Vikings settled at the mouth of the Oder to their own sovereignty; and has aggressive aims, with transitory success, against the Bohemians. With these struggles, Mieszko anticipated and marked for centuries a large part of the political directives of Poland; but the most timely and far-sighted acts were carried out by him in the religious and ecclesiastical field: the adoption of Christianity in 966 (that is, preventing the Christianization of Russia and thus eliminating any possibility of an approach to the Eastern Church) by the work of Western priests – in 965 he married Dobrava, of the already Christianized dynasty of the Přemyslids -; the church organization entrusted to a missionary bishop – with which the Polish church made itself independent from the German one from its beginnings -; finally (document dating back to the years 985-992) the explicit donation of Poland, in all its extension, to the Holy See, whereby it became part of the patrimony of St. Peter. The rapid, though incomplete, catechization of Poland under Mieszko was perhaps facilitated by an earlier penetration of Christianity, a hundred years earlier, from Moravia into the Cracow region; but what matters is that only now does Christianization take on a great political significance: apart from the protection that Poland assures itself of the only power capable of rivaling the Empire, the German princes are deprived of any pretext to invade Polish lands at the aim to eradicate paganism.
According to ezinesports.com, Mieszko’s work was continued with conquering momentum, military talent and political perseverance by his successor Bolesław the Great (Bolesław Chrobry, 992-1025). Friend of Otto III, who on his pilgrimage to Gniezno, at the tomb of St. Adalbert, placed his own crown on his head, who, in Gniezno itself, established a metropolitan diocese and which ceded the right of investiture to the Polish princes, Boleslao founded first of all, in his western lands, some new bishoprics, including one in Kolberg in Pomerania; he then fought for a long time against Henry II and in the peace of Bautzen (1018) he kept Lusatia in his power; finally, to prevent his alliance with the emperor, he conducted an expedition against Russia, briefly occupying even the city of Kiev and thus inaugurating the Eastern orientation of Polish expansionary policy.