by the eleventh century the formation of a strong monarchy on the compact territory of the Odra and the Vistula river-basins, extending south as far as the Sudetes and the Carpathian Mountains, and north as far as the Baltic Sea, had been completed; the process of Christianization was well advanced, and Poland could already boast her own saint in the person of Bishop Wojciech (Adalbert) of Prague, who had been exiled from Bohemia; the Polish rulers had established good relations with the western empire and had developed contacts with distinguished personages of the time. In the year 1000 the emperor Otto III arrived in Poland to elevate Gniezno (Gnesen) to the level of archbishopric, thus creating the first Polish ecclesiastical province, to which the apostolic see had given its consent earlier. The ruler of Poland, Prince Boleslaw Chrobry (Boleslaw the Brave) of the Piast dynasty, managed to win Otto’s trust by supporting his project of the ‘revival of the Roman empire’ and was called ‘an aide’ (cooperator) of the empire, in which, it seems, he stood a good chance of representing one of its four basic territorial parts (Roma, Galia, Germania, Sclavinia). But the death of Otto III in 1002 and the changes in German policy under Henry II on the one hand and Boleslaw’s expansive plans towards Milsko (Milzi), Łużyce (Lusatia) and Bohemia on the other led to a long Polish-German war, which was fought in three stages (1003–5, 1007–13,1015–17) and ended with a peace treaty in Budziszyn (Bautzen) in 1018.