Mieszko II Lambert Gniezno Cathedral. Contemporary German chroniclers considered this to be an abuse of power on the part of the Archbishop, which was made necessary by the existing political situation. After his father's death, Mieszko inherited a vast territory, which in addition to Greater Poland, Lesser Poland, Silesia and Gdansk Pomerania also included Western Pomerania, as well as Lusatia, Red Ruthenia and territory of present-day Slovakia. Whether Moravia was still under his reign or was lost earlier is disputed. Once his solo reign had begun, as an important Central European ruler, he was now very important to the Holy Roman Empire. Later
Mieszko I of Poland socially connected primarily by tribal structures. It appears that the elders cooperating with the Duke first felt the need for super-tribal unity, as expansion allowed them to broaden their influence. Mieszko and his people were described around 966 by Abraham ben Jacob, a Sephardi Jewish traveller, who at that time visited the Prague court of Duke Boleslav I the Cruel. Abraham presented Mieszko I as one of the four Slavic "kings", reigning over a vast "northern" area, with a highly regarded and substantial military force at his disposal. More precise contemporary records regarding Mieszko were compiled by Widukind of Corvey,