However , following Roger 's death in 1154 , there was a revolt on the mainland , led by Robert II of Basunvilla , cousin of the new king William I .
When Alfonso died in 1144 , Roger made his fourth son William prince .
Following Roger 's death in 1154 , there was a revolt on the mainland , led by Robert II of Basunvilla , cousin of the new king William I .
When Alfonso died in 1144 , Roger made his fourth son William prince .