Last quarter of 18th century brought revival of research on the region’s history. The year 1335 was still one of the unquestionable turning point in the history of Silesia. Then Casimir III the Great accepted John the Blind’s claims for Silesian duchies that had already paid homage to the King of Bohemia. In the same time, after the death of childless duke Henry VI, the duchy of Wrocław became a part of the Kingdom of Bohemia. Two 18th century Silesian historians Karl Ludwig von Klöber und Hellscheborn, and Friedrich Wilhelm Pachaly stressed in their works that the event was an important stage of the process of keeping internal integrity of Silesia. They noticed that at the beginning of 14th century Silesian Piasts could not survive as independent rulers. They were not able to cooperate each other. This brought an excessive feudal fragmentation and their weak position. The Polish Kings Ladislaus I the Elbow-high and Casimir III the Great neglected both the Silesian dukes and Silesia as a land. Therefore the Silesian Piasts turned to John the Blind. When his successor Charles IV established Bohemian Crown, Silesia was one of its lands. Both historians, mentioned earlier, were sure that the decision confirmed that Silesia was a separate region and opened the way to create own identity towards Poland and Czech lands in the future