The Medieval Elbe
Slavs and Germans on the Frontier

Wichmann

Wid III.66


III.66. Therefore Count Gero, not unmindful of the oath, since he had seen Wichmann be accused and had recognized his guilt, restored him to the barbarians from whom he had received him. Received by them gladly, he ground down with frequent battles the barbarians living further away. He twice overcame king Mieszko, in whose power were the Slavs who are called Licicaviki and killed his brother, and wrenched great booty from him.

Analysis

This is, along with Ibn Ya'qub's travelogue, the earliest attestation of Mieszko, ruler of the Poles.  The Licicaviki have not been identified by scholars.