Mieszko I of Poland Abraham ben Jacob. According to him, Mieszko I had fought against the Weltaba tribe, commonly identified with the Veleti. Wichmann the Younger, a Saxon nobleman who was then a leader of a band of Polabian Slavs, defeated Mieszko twice, and around 963 a brother of Mieszko, whose name is unknown, was killed in the fighting. The frontiers at the mouth of the Oder River were also desired by the German margraves. In addition, the Veleti Bohemia, which at that time possessed Silesia and Lesser Poland regions, constituted a danger for the young state of the Polans. The chronicle of Thietmar
Mieszko I Tanglefoot the Sandomierz nobles captured in the battle). On 22 March 1201 Jarosław of Opole died. The Duchy of Opole was then inherited by his father Bolesław the Tall, with whom the late Duke was recently reconciled. Bolesław the Tall died only nine months later, on 7/8 December 1201, leaving all his lands to his eldest (and only) surviving son Henry I the Bearded. Mieszko was determined to obtain Opole and made a surprise attack at the beginning of 1202. The Duke managed to obtain Opole, which was from then on definitely joined to his lands. Despite this victory, Mieszko wanted