History

County Clare was formerly part of the kingdom of Thomond (north Munster) which comprised, in addition to Clare, portions of Limerick, Offaly and Tipperary. Clare formed, however, the central or core territory of the old kingdom and by the time the earldom of Thomond was created in the 16th century, its extent was limited, more or less, to the present county

The earliest inhabitants of Clare are part of pre-history and there is, therefore, no certain knowledge of who they were or where they came from. The Leabhar Gabhála, or Book of Invasions, a compendium of largely mythological accounts of successive occupations by overseas land-seekers, connects Clare with the Fir Bolg.
This people, after various adventures, settled in the west of Ireland and are identified with Magh Adhair in Clare, Lough Cutra in Galway, and Dún Aongus in the Aran Islands.

In historical times the first figure to emerge from the mists was a certain Cas, a contemporary of St. Patrick (5th century) and a member of the Munster royal family. His descendants occupied territory between Cashel and Limerick. Early in the 10th century the Dal gCais (sept or tribe of Cas), or Dalcassians, began to work their way across the Shannon into Clare.
An uncle of Brian Boru, named Lachtna, established himself just north of Killaloe at Crag Liath (the grey rock) about 950. He was succeeded first by his nephew Mahon and then in 975 by a second nephew, the great Brian Boru. Besides extending their overlordship in Clare, both Mahon and Brian conducted an active and ultimately successful campaign against the Norsemen of Limerick and Scattery Island. The campaign became a nationwide struggle, culminating in the great victory at Clontarf, near Dublin, in 1014.

Brian had become High-King of Ireland in 1002, built Kincora as his royal residence in 1012, rebuilt the churches of Killaloe and Inis Cealtra (Holy Island), erected bridges and made roads. He was the greatest of pre- Norman kings. Brian Boru was killed at Clontarf in his battle against the Danes of Dublin and following his death the O'Brien hegemony of Munster was broken, while the semblance of national unity he had managed to create soon disappeared. The O'Briens, now limited to north Munster or Thomond, kept up hostilities with varying success against the O'Conors of Connaught, until it occurred to Donal Mor O'Brien, the incumbent chief, to call in aid a new group of invaders. In 1172 he swore allegiance to Henry II of England and got the help of a party of Norman mercenaries in pursuit of his war aims. His successor also did homage to King John at Waterford and was rewarded with the kingship of Thomond.
But the Normans balanced the account by expelling him from Limerick, whereupon he retired to Clonroad near Ennis, which remained the O'Brien headquarters for some centuries.

Despite some initial attempts the Normans failed to secure any permanent footing in Clare. A son of the Earl of Gloucester, Thomas de Clare, (the family name of 5trongbow, incidentally, neither derived from nor bestowed on the county) managed to occupy part of southern Clare, where he built the castle of Bunratty in 1277. But the de Clares were expelled following the battle of Desert O'Dea in 1318 and the English did not reappear in the county for more than two centuries.

The accession of Henry Vlll in 1534 and his acknowledgement as King ot Ireland marked the revival of English power in those parts of Ireland outside the, Pale the area round Dublin where the King's writ ran. The re-assertion of royal dominance was felt in Clare, where Morrogh O'Brien became Earl of Thomond in 1541, when it was detached from Munster and placed under the Presidency of Connaught.
It did not rejoin Munster until the Restoration in 1660. The O'Briens remained loyal to the Crown, more or less, during the confused period up to the Cromwellian conquest. The Earl of Thomond and the Baron of Inchiquin took arms against the Great O'Neill and Red Hugh O'Donnell in the Elizabethan wars. In the 1641 uprising, the Earl of Thomond did his best at first to protect english interests, but many prominent O'Briens, MacNamaras and others of that extended family sided with the Catholic cause and took part in the Confederation of Kilkenny.

When the civil war broke out in England, Barnabas, Earl of Thomond, leaned towards Charles I, but in 1646 reluctantly admitted a parliamentary garrison to the great castle of Bunratty.
The castle was shortly afterwards recovered by the confederate army, but was finally taken by Ireton in the Cromwellian overthrow. The rest of Clare followed. The Cromwellian wars left Clare in ruins, racked by famine and depopulated. The county, as part of Connaught, became a refuge for the disposessed Irish from the rest of the island. The Earl of Thomond went to England where he died in 1657. Morrogh, Baron Inchiquin, an able general, put up some resistance to the parliament forces but eventually fled to France where he remained until the Restoration. He was rewarded by Charles II with the presidency of Munster.