Gaelic nobility of Ireland in the context of "Anglo-Irish"

Ireland was conquered by the Tudor monarchs of England in the 16th century. The Anglo-Normans had conquered swathes of Ireland in the late 12th century, bringing it under English rule. In the 14th century, the effective area of English rule shrank markedly, and from then most of Ireland was held by native Gaelic chiefdoms. Following a failed rebellion by the Earl of Kildare in the 1530s, the English Crown set about restoring its authority. Henry VIII of England was made "King of Ireland" by the Crown of Ireland Act 1542. The conquest involved assimilating the Gaelic nobility by way of "surrender and regrant"; the confiscation and colonisation ('plantation') of lands with settlers from Britain; imposing English law and language; banning Catholicism, dissolving the monasteries, and making Anglican Protestantism the state religion.

The Tudor policies in Ireland sparked the Desmond Rebellions (1569–1573, 1579–1583) and the Nine Years' War (1594–1603). Despite Spain sending an armada to support the Irish Catholics during the Anglo-Spanish War (1585–1604), by 1603 the entire country was under English rule. The Flight of the Earls in 1607 largely completed the destruction of the Gaelic aristocracy and left the way open for the Plantation of Ulster, which established a large British Protestant population in the north. Several people who helped establish the plantations of Ireland also played a part later in the early colonisation of North America, particularly a group known as the West Country Men.

The Irish nobility could be described as including persons who do, or historically did, fall into one or more of the following categories of nobility:

• Gaelic nobility of Ireland: descendants in the male line of at least one historical grade of king (Rí).
• Hiberno-Norman or Old English (Ireland) nobility: descendants of the colonisers who came to Ireland from Wales, Normandy and England after the Norman invasions of England and Ireland in 1066 and 1169–71, respectively.
• Peerage of Ireland, whose titles were created by the English and later British monarchs of Ireland in their capacity as Lord or King of Ireland.

These groups are not mutually exclusive. There is some overlap between the first two groups (prior to the Treaty of Limerick), and a lesser degree of overlap between the last two groups (prior to independence from the United Kingdom). Such overlaps may be personal (e.g. a Gaelic noble who was "regranted" his titles by King Henry VIII of England), or they may be geographical (i.e. different noble traditions co-existing in neighbouring parts of the country, which were only distinguished by the date when they finally fell under the Dublin Castle administration).

The Protestant Ascendancy (Irish: An Chinsealacht Phrotastúnach; also known as the Ascendancy) was the sociopolitical and economical domination of Ireland between the 17th and early 20th centuries by a small Anglican ruling class, whose members consisted of landowners, barristers, politicians, clergymen, military officers and other prominent professions. They were either members of the Church of Ireland or the Church of England and wielded a disproportionate amount of social, cultural and political influence in Ireland. The Ascendancy existed as a result of British rule in Ireland, as land confiscated from the Irish Catholic aristocracy was awarded by the Crown to Protestant settlers from Great Britain.

During the Tudor conquest of Ireland, land owned by Irish nobles was gradually confiscated by the Crown over several decades. These lands were sold to colonists from Great Britain as part of the plantations of Ireland, with the province of Ulster being a focus in particular for colonisation by Protestant settlers after the Battle of Kinsale. These settlers went on to form the new aristocracy and gentry of Ireland, as the Gaelic nobility had either died, fled with the Flight of the Earls or allied with the Crown. They eventually came to be known as the Anglo-Irish people. From the 1790s the phrase became used by the main two identities in Ireland: nationalists, who were mostly Catholics, used the phrase as a "focus of resentment", while for unionists, who were mostly Protestants, it gave a "compensating image of lost greatness".

Fianna (/ˈfiːənə/ FEE-ə-nə, Irish: [ˈfʲiən̪ˠə]; singular Fian; Scottish Gaelic: Fèinne [ˈfeːɲə]) were small warrior-hunter bands in Gaelic Ireland during the Iron Age and early Middle Ages. A fian was made up of freeborn young men and women, often from the Gaelic nobility of Ireland, "who had left fosterage but had not yet inherited the property needed to settle down as full landowning members of the túath". For most of the year they lived in the wild, hunting, cattle raiding other Irish clans, training, and fighting as mercenaries. Scholars believe the fian was a rite of passage into manhood, and have linked fianna with similar young warrior bands in other early European cultures.

They are featured in a body of Irish legends known as the 'Fianna Cycle' or 'Fenian Cycle', which focuses on the adventures and heroic deeds of the fian leader Fionn mac Cumhaill and his band. In later tales, the fianna are more often depicted as household troops of the High Kings.