This new generation of people in England became very dissatisfied about the productivity of Ireland and the Reformation became a further excuse to invade. Between 1580 and 1690 Ireland was three times devastated: first by the Elizabethan conquest; then by the rising of 1641, followed by the Cromwellian conquest and settlement; and finally by the Williamite Wars. This new departure began with Henry V111. Before his reign, the English crown was powerless in most parts Ireland. However, following Henry’s successor Tudor Monarchs Edward V1, Mary and Elizabeth the entire island was completely under English rule. Not only did they bring the whole country for the first time under the control of a central government, but they ensured that that government would be an English one. Each upheaval represented the violent rejection by the old Irish order of the new order which its English exponents sought to impose. Apart from the immediate destruction of men and materials, which in each case was in frightful scale, each wave of havoc exacerbated the enmity between the two sides and together they made impossible any relationship of the conqueror and conquered.

The history of the seventeenth century precluded compromise between planters and the Irish. To the former it made it clear that their position in Ireland was only secure only as long as they commanded, or could obtain from England, the force necessary to maintain it. For the latter it removed hope of alleviation other than by complete overthrow of the newly imposed political, economic and social system. It gave rise not alone to two classes but two nations, between them there could only exist friction and enmity. Political or economic co-operation was made almost impossible. The repercussions saw the re-distribution of 250,000 acres of land in Munster the Flight of the Earls and their lands taken over by the Crown. Six counties Donegal, Derry, Tyrone, Armagh, Fermanagh and Cavan – more than three million acres in all were taken over. About 600,000 acres of the best land was set aside for new settlers. The remainder made up of moor, woodland, bog and marsh was left to the peasant Irish. The new settlers were given estates of 1000, 1,500 and 2,000 acres. All were compelled to take the Oath of Supremacy, that is an oath recognizing the King as head of the Church.  Niall O’Donnell was given land in Co. Mayo, the O’Reillys were left a small estate in Cavan. Conor Maguire retained a portion of his land in Fermanagh, and Magennis did in Co. Down. The new settlers or colonists were English Protestants and Scottish Presbyterians.

Following on the clash between the new order, as represented by the Elizabethan and Cromwellian conquerors, and the old order was unusually bitter. Exasperating as well as complementing and reflecting the fundamental economic differences were the religious and cultural differences. The old order was Catholic and Gaelic, some Anglo Irish Land owners refused to convert to Protestantism, the vast majority complied to protect their estates, while the new planters were Protestant and very English. In the words of Tawney: “the elements were so alien that assimilation was out the question (and) the result was a wound that festered for three centuries”.