County Limerick was the ancient home of the Uí Fidgeinte, Uaithne, Corca Oiche, Orbraige, Uí Cairbre Eaodhe, Uí Conaill Gabra, Muscraige Luachra, and Eoghanacht Aine. The Viking settlement of Limerick was formed during the 9th and 10th centuries. Some of the cantreds that existed about the time of the Norman arrival included Carrigoginniol, Uaithne, Cairbre Aobhdha, Uí Conaill Gabhra, and Connalla.
Of the tribes mentioned by Ptolemy, the Coriondi appear to have inhabited this portion of Ireland; LIMERICK, and although from a very early period it was included in the native kingdom or principality of Thomond, it is said to have had at one time a separate political existence, under the name of Aine-Cliach, or Eoganach-Aine-Cliach, and to have been divided into five cantreds, governed by subordinate chieftains. That of Carrigoginniol belonged to the O'Kiarwicks, and afterwards to the O'Briens, whence the name Pubblebrien was given to the barony; Uaithney, now the barony of Owneybeg, belonged to the O'Ryans; Cairbre Aobhdha, or Kenry, to the O'Donovans; Hy Cnocnuil Gabhra, now the barony of Upper Connello and Coshma, to the McEneirys and O'Sheehans; and Connalla, now Lower Connello, to the O'Kinealys and O'Thyans. At the time of the English invasion, the O'Hurleys, MacSheehys, O'Gormans, O'Collins, O'Coins, O'Scanlans, and O'Hallinans, were among the principal families. About the middle of the ninth century, the Ostmen made themselves masters of the city of Limerick and of the island of Inniscattery, in the Shannon; and maintained their power until the commencement of the eleventh century, when Brien Boroimhe, King of Thomond, compelled them to become his tributaries. The city subsequently became the chief seate of the rulers of Thomond, of the O'Brien family, whence their country was often called the Kingdom of Limerick.
The Déise Becc (Déisi Bicce) were noted about the baronies of Small County and Coshlea in southeast county Limerick. The parish of Athneasy, alias Áth na nDéise, is said to derive its name from the Déise Becc. They are sometimes referred to as 'In Déis Deiscirt' to distinguish them from their northern neighbors, the 'In Déis Tuaiscirt' who are represented in the Dal gCais. However the terms déisi tuaiscirt and déise deiscirt were also applied to the O'Felans and O'Brics of north and south Decies (Dési Muman), respectively.
Corca Oiche (Oche, Oidhce) was located near the Abbeyfeale district of County Limerick. O'Macasa (e.g. MacKessy and Maxey) are cited as a chief of Corca Oiche. St Molua was born in Ardagh of the ruling sept of Corca Oice in 554 A.D. MacFirbis cites a genealogy from the mythic Fionn Mac Cumhaill, son of Baoisgne, son of Oiche (of Corca Oiche ua fFidhgente).
King John's Castle in Limerick and the river Shannon. The first stronghold in Limerick was built by Vikings in 922. Vikings were soon defeated and the city fell into Celtic hands. In 1174, after Anglo-Normans arrived in Ireland, local lord Domhnall Mor O'Brien burned the city to the ground to keep it from their hands. The new invaders rebuilt the city and built a stone castle around 1200. Remains of the early Viking fortifications were recently uncovered and can be seen in the castle's underground.
The Desmond castle was founded by William de Burgo in 1199, Askeaton castle
became the dwelling place of the King of Munster. In 1287 the Castle was on
the possession of Thomas De Clare. King Edward II, who reigned from 1298 to
1328, granted it to Robert de Welle on 1318. The Earls of Desmond made askeaton
castle their principal dwelling place from 1348. Today's structure dates from
the 15th century. the English forces marched against the Desmond's in Oct
1579. they considered the Desmond's as traitors after the refused to accept
English rule. On august 1642, Askeaton castle was captured by Colonel Purcell
of the Confederate Catholics and the council of his majesty for the province
of Munster. All arms, munitions, garrison horses and goods belonging to the
Catholics were surrendered. Askeaton castle was finally dismantled in 1652
by the Cromwellian forces . 