The military campaigns of the reformed Livonian Order against Lithuanians were still unsuccessful. Even with support from the Teutonic Order, the Christian Livonians suffered major defeats in the battles of Durbe (1260), Karuse (1270), and Aizkraukle (1279). These losses weakened the Teutonic Order, allowing for the Great Prussian Uprising. When the converted king of Lithuania, Mindaugas, was assassinated in 1263, the region entered an era of instability. Lithuanians supported the Prussian uprisings and arranged military raids together with Prussians and Yotvingians. These included the 1264 siege of Vėluva (Wehlau) castle in Sambia during the reign of Treniota and the revenge taken against Poland for the Yotvingians, led by Vaišvilkas and Švarnas.