Mieszko I of Poland by him. As Widukind of Corvey wrote, Mieszko ruled over the tribe called the "Licicaviki", now commonly identified with the Polabian Lubusz Land. Having the control over those more western (in respect to the original homeland of the Polans) tribes, Mieszko had entered the German sphere of influence. In 963 the German Margrave Gero conquered territories occupied by the Polabian Lusatian and Słupian tribes, and as a result came into direct contact with the Polish state. At the same time (about 960) Mieszko I began his expansion against the Velunzani and Lutici tribes. The war was recorded by the chronicler
Mieszko I of Poland the Polabian Slavs. On the other hand, the supporters of the Gero's invasion theory believe that the Margrave did actually carry out a successful invasion, as a result of which Mieszko I was forced to pay tribute to the Emperor and also was compelled to adopt Catholicism through the German Church. The thesis that proposes the introduction of Catholicism as a result of this war finds no confirmation in German sources. The homage is then a separate issue, since, according to the chronicle of Thietmar, Mieszko actually paid tribute to the Emperor from the lands "usque in Vurta fluvium" (up