Complex sentence: Throughout the rest of The Third Age, Umbar was home a new generation of'Corsairs of Umbar', ruled by a'Captain of the Haven', and these were cruel slavers, who raided the coasts of Belfalas and Anfalas.
Split into simpler sentences: Throughout the rest of The Third Age, Umbar was home to new "Corsairs of Umbar", ruled by the "Captain of the Haven". These new Corsairs were cruel slavers, who raided the coasts of Belfalas and Anfalas.