ヘンリク1世
Given the increased power of Duke Henry I the Bearded during the 1220s, Casimir I's geopolitical position became more complicated. He took the only possible decision: close cooperation with his Lower Silesian cousin. The content of the agreement is unknown, but certainly during the unsuccessful trip of Henry I the Bearded against Kraków in 1225, troops of Opole-Racibórz were with him. This fact attests to the presence of political emigrants from Lesser Poland after 1225 in Opole-Racibórz (for example, the Gryfici family). After this year, the help of emigrants, like Klement of Brzeźnica (member of the Gryficis)-who took on part of the costs of building the city walls of Opole-proved to be good for Casimir I. The alliance with Henry I the Bearded also gave the Duke of Opole-Racibórz territorial benefits: in 1227 as a result of the confusion reigning in Poland following the death of High Duke Leszek I the White, Casimir I annexed the frontier fortress of Czeladź.