For about 20 years after the Great Potato Famine, political agitation was subdued, and emigration continued to reduce the population every year. The landowners also suffered severely from an inability to collect rents, and there was a wholesale transfer of estates to new owners. Evictions were widespread, and cottages were demolished at once by the landlords to prevent other impoverished tenants from occupying them. The flow of emigrants to the United States was encouraged by invitations from Irish people already there, and in England the new industrial cities and shipping centres attracted large settlements of poor migrants from Ireland.
The outbreak of the French Revolution had effected a temporary alliance between an intellectual elite among the Presbyterians and leading middle-class Catholics; these groups, under the inspiration of Wolfe Tone, founded in 1791 a radical political club, the Society of United Irishmen, with branches in Belfast and Dublin.
Although the 1798 rebellion failed and was savagely suppressed, the threat to British security posed by the alliance between their French enemies and the Irish rebels prompted the British government to tighten its grip on Ireland. The prime minister, accordingly planned and carried through an amalgamation of the British and Irish parliaments, merging the two kingdoms into the United Kingdom of Great Britain and Ireland. Despite substantial opposition in the Irish Parliament to its dissolution, the measure passed into law, taking effect on January 1, 1801. To Grattan and his supporters the union of Ireland and Great Britain seemed the end of the Irish nation.
Social, economic, and cultural life in the 17th and 18th centuries - Except on the Ulster plantations, the tenantry was relatively poor in comparison with that of England and employed inferior agricultural methods. Over large parts of the east and south, tillage farming had given way to pasturage. In the north of Ireland, a similar tendency created a decline in the demand for labour and led in the early 18th century to the migration of substantial numbers of Ulster Scots to North America.
Not only the Catholic majority but also the Presbyterians and other Nonconformists, whose combined numbers exceeded those of the established church, were excluded from full political rights, notably by the Test Act of 1704,
Paul Cullen (1803 - 1878, Dublin) was archbishop of Armagh (1850–52) and Dublin (1852–78) and became the first Irish bishop to be elevated to the rank of cardinal. Cullen’s reforms of the Roman Catholic Church in Ireland in the mid-19th century are credited with shaping the country’s religious character well into the 20th century.
St. Patrick’s College at Maynooth, Roman Catholic seminary was established in 1795 on the site of a college founded by the earl of Kildare in the 16th century and is now part of the National University of Ireland.