Thirty years later the natives of Ulster found their opportunity, and wreaked on their landlords, in the massacre of 1641, vengeance for a generation of robbery and oppression. There ensued a decade of indescribable confusion, in which native Irish, Anglo-Irish, Ulster Scots, English parliamentarians, and Royalists fought one another, until Cromwell repaid the massacre of 1641 by those of Drogheda and Wexford, and by a further process of expropriation called the Cromwellian Settlement. More than two-thirds of Irish land had now passed into the hands of Englishmen; and although the Cromwellians had to disgorge a part of their spoil at the Restoration, it was estimated by Sir William Petty in 1664 that not more than one-third of the land belonged to the native Irish, including in that category the descendants of Anglo-Norman families; of the remainder, about half belonged to Elizabethan and Jacobean planters, and half to the Cromwellians. Nor was the process yet complete: the new expropriation was followed in 1689-90 by yet another attempt on the part of the Irish to recover their inheritance, and the failure of that attempt by further confiscation. At the beginning of the eighteenth century three-quarters of the land was owned by the English garrison, and the progress of the century was marked by fresh evictions. Political reasons had ceased, but economic causes supplied their place; and wide stretches of pasture were needed in order that the landlords might turn _their_ property to the most profitable grazing purposes. Only land that would not do for cattle was left to the Irish peasants; from the bogs there looked up, from the barren hills there looked down, the Roman Catholic disinherited upon the smiling meadows of their Protestant supplanters.