Complex sentence: The castle probably spent the next fifty years passing from one feudal ruler to another: from Hywel to Cadwaladr in 1144, and then ceded to Roger de Clare, 3rd Earl of Hertford in 1158, who garrisoned it.
Split into simpler sentences: The castle probably spent the next fifty years passing from one feudal ruler to another. From Hywel to Cadwalader in 1144, and then ceded to Roger de Clare, 3rd Earl of Hertford in 1158, who garrisoned it.