Bernard William was the Count of Berga (from 1094, as Bernard II) and Count of Cerdanya (from 1109).

A son of William I of Cerdanya

William I of Cerdanya

William I Raymond was the count of Cerdanya and Berga from the year of his birth till that of his death, giving up Berga a year earlier to his son William-Jordan....

 and Sancha of Barcelona, he inherited Berga from his father in 1094. On the death of his brother William-Jordan

William-Jordan

William II Jordan was the Count of Berga beginning in 1094, the Count of Cerdanya beginning in 1095, and Regent of the County of Tripoli beginning in 1105....

 in 1109, he inherited Cerdanya. In 1111, after the death of Bernard III of Besalú, he opposed the integration of Besalú into the County of Barcelona as it was technically a feudatory of Cerdanya, as were Fenollet and Vallespir

Vallespir

Vallespir is a historical Catalan comarca of Northern Catalonia, part of the French Département of Pyrénées-Orientales. The capital of the comarca is Ceret, and it borders Conflent, Rosselló, Alt Empordà, Garrotxa and Ripollès...

. However, he eventually agreed to abdicate these counties to his cousin and friend Raymond Berengar III of Barcelona. When he himself died seven years later without heirs, Cerdanya passed to Barcelona.
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