 The religious struggles of the 17th century left a deep sectarian division in Ireland . Religious allegiance now determined the perception in law of loyalty to the Irish King and Parliament . After the passing of the Test Act 1672 , and with the victory of the forces of the dual monarchy of William and Mary over the <unk> , Roman Catholics and <unk> Protestant Dissenters were barred from sitting as members in the Irish Parliament . Under the emerging <unk> Laws , Irish Roman Catholics and Dissenters were increasingly deprived of various and <unk> civil rights even to the ownership of hereditary property . Additional <unk> punitive legislation followed 1703 , <unk> and <unk> . This completed a comprehensive systemic effort to materially disadvantage Roman Catholics and Protestant Dissenters , while <unk> a new ruling class of Anglican conformists . The new Anglo @-@ Irish ruling class became known as the Protestant <unk> . 
