Irish clans in the context of "Gaelic Ireland"

This article lists some of the attested Gaelic kingdoms of early medieval Ireland prior to the Norman invasion of 1169-72.

For much of this period, the island was divided into numerous clan territories and kingdoms (known as túatha). These túatha often competed for control of resources and thus they continually grew and shrank (in both size and number). In addition to kingdoms or túatha, Gaelic Ireland was also divided into five prime overkingdoms (Old Irish cóiceda, Modern Irish cúige). These were Ulaid (in the north), Connacht (in the west), Laighin (in the southeast), Mumhan (in the south) and Mide (in the centre).

The Irish (Irish: Na Gaeil or Na hÉireannaigh) are an ethnic group and nation native to the island of Ireland, who share a common ancestry, history and culture. There have been humans in Ireland for about 33,000 years, and it has been continually inhabited for more than 10,000 years (see Prehistoric Ireland). For most of Ireland's recorded history, the Irish have been primarily a Gaelic people (see Gaelic Ireland). From the 9th century, small numbers of Vikings settled in Ireland, becoming the Norse-Gaels. Anglo-Normans also conquered parts of Ireland in the 12th century, while England's 16th/17th century conquest and colonisation of Ireland brought many English and Lowland Scots to parts of the island, especially the north. Today, Ireland is made up of the Republic of Ireland (officially called Ireland) and Northern Ireland (a part of the United Kingdom). The people of Northern Ireland hold various national identities including Irish, British or some combination thereof.

The Irish have their own unique customs, language, music, dance, sports, cuisine and mythology. Although Irish (Gaeilge) was their main language in the past, today most Irish people speak English as their first language. Historically, the Irish nation was made up of kin groups or clans, and the Irish also had their own religion, law code, alphabet and style of dress.

On 14 September [O.S. 4 September] 1607, Irish earls Hugh O'Neill, Earl of Tyrone, and Rory O'Donnell, 1st Earl of Tyrconnell, permanently departed Rathmullan in Ireland for mainland Europe, accompanied by their extended families, retinue, followers and fellow nobility, numbering about 100 people. The earls were patriarchs of the two most powerful clans in Ulster—the O'Neill and O'Donnell clans—and their permanent exile is seen to symbolise the end of Gaelic Irish society. This event is known as the Flight of the Earls (Irish: Imeacht na nIarlaí).

Both earls fought against the English Crown in the Nine Years' War (1593–1603), which ended with their surrender. The newly crowned James VI and I granted the earls generous peace terms which allowed them to retain their lands and titles. Many courtiers were unsatisfied with the king's leniency, and hostility towards the earls from British officials gradually increased over time. The implementation of English law in Ireland led to financial difficulties for both earls as well as a major land rights dispute between Tyrone and his vassal Donnell Ballagh O'Cahan, which was weaponised by officials such as Arthur Chichester, John Davies, and George Montgomery.

During the Tudor conquest of Ireland (c.1540–1603), "surrender and regrant" was the legal mechanism by which Irish clans were to be converted from a power structure rooted in clan and kin loyalties, to a late-feudal system under the English legal system. The policy was an attempt to incorporate the clan chiefs into the English-controlled Kingdom of Ireland, and to guarantee their property under English common law, as distinct from the traditional Irish Brehon law system. This strategy was the primary non-violent method for Crown officials in the Dublin Castle administration to subjugate Irish clan leaders during the conquest. It was an unanticipated consequence to be required to pay fealty in currency instead of trade labor or commodities. The process of "surrender and regrant" thus created new, unfamiliar debt structures among the Irish, and these debts had social and political consequences.

McMahon, also spelt MacMahon (older Irish orthography: Mac Mathghamhna; reformed Irish orthography: Mac Mathúna), were different Middle Age era Irish clans. Their name is derived from the Gaelic Mac Mathghamhna meaning 'son of the bear'. According to historian C. Thomas Cairney, the MacMahons were one of the chiefly families of the Dal gCais or Dalcassians who were a tribe of the Erainn who were the second wave of Celts to settle in Ireland between about 500 and 100 BC. The same historian stated that another group of McMahons were a chiefly family of the Oirghialla or Airgíalla tribe who were in turn from the Laigin tribe who were the third wave of Celts to settle in Ireland during the first century BC.