the senioral principle was soon broken, with władysław ii attempting to increase his power and his younger half-brothers opposing him. after initial success (taking over the łęczyca land after the death of salomea), he was eventually defeated and expelled from poland in 1146. with the help of emperor frederick i barbarossa his sons managed to retain the silesian province in 1163, losing the seniorate, which had passed to their uncle bolesław iv. this led to a period of nearly 200 years of poland's feudal fragmentation; the estrangement of the silesian piasts deepening after the death of duke henry ii the pious at the disastrous battle of legnica in 1241.