Thomond was the territory of the Dál gCais, comprised most of Clare and parts of Limerick and Tipperary. The MacCarthys of Muskerry and Cork were Kings of Desmond until the fourteenth century when the Fitzgeralds were appointed the lands after the Anglo-Norman invasion. By the 13th century territorial names included the Decies, Gal-tir, Hy-Fodhladha, and Uactar Tire. After the anglo-Norman invasion the Fitzgeralds were the ruling family in the area. King John incorporated Youghal about the yeare 1209 and it has now about 6,000 inhabitants. The founder of the clan was an Irish warlord named Gillean na Tuaighe ("Little Giles of the Battleaxe") Fitzgerald, who lived in the reign of Alexander III of Scotland (1249-1286). He was originally a chieftain of the Fitzgeralds, but soon broke his sept off to form his own clan. In 1299 John de Mohun of Dunster (La Manche of the English Channel), co-heir of the Marshall family, held lands in Kildare. South Town, comprising the parish of St. Petrox, and formerly belonging to the Fitzstephen, Fleming, Mohun, Carew (Bampton), and Southcote families. Mohun's Ottery or Ottery Fleming in Luppit parish and Axminster hundred. The monastic church of Cleeve was certainly built as early as 1232; Newenham 1246.
Ormond territory comprised Kilkenny and north Tipperary. The name Urmhumhan means east Munster and this territory was also known as Muscraige Thire. Ossory territory comprised Kilkenny and surrounding areas. It was occupied around the second century by the Osraige, descendants of Aengus Osrithe. In the fifth century the nearby tribes of the Déisi and the Corca Laoidhe, conquered South Ossory. The Ó Cinnéide (Kennedys) were Lords of Ormond and later the Butlers were Earls of Ormond.
- [Annals of Clonmacnoise 934; Annals of the Four Masters 939 AD; Chronicon Scotorum 940 AD; Annals of Inisfallen 941 AD; ] Ceallachan defeats the Ossorie (east Munster). Mortaugh mcNeale (of the Leather Cloaks) with the forces of the north went to Ossory and Desies and preyed them. Ceallachan defeats the Déisi in a battle: 941 AD. the Déisi combined with the Osraige against Ceallachan and gained a battle. Taking advantage of this, Muirchertach mac Neill in the winter of 941 AD makes a surprise wintertime circuit of Ireland with 1000 men and takes Ceallachan and others hostage. They may have been held at Aileach for 5 months, when Donnchadh, (Donnogh mcMelaghlin) the king of tara or Ireland refused the hostages, or as long as until Muirchertach's death in 943 AD. Muirchertach son of Niall, royal heir of Ireland dies a violent death "at the hands of the heathens" (Norse) in 943 AD. After his release, Ceallachan defeats the Dal Cais led by Cennedigh (Kennedy), son of Lorcan, father of Brian Boru at Magh-duine (Moyddwyne): 944 AD.
- [Circuit of Ireland 944 AD; Annals of Ulster 943] Donnchadh, or Donough, son of Flann, the high king of Tara or Ireland dies 944 AD (25 year reign). Cennedigh, son of Lorcan, King of Dal-Cais, dies. However, according to Caithreim Ceallachain Caisil, by 951 AD Donnchadh, king of Tara was dead (he died in 944) and the saga clearly indicates several times that he was alive during the events at Dundalk, Dublin, and Leinster. This suggests a much earlier date for the events in the saga. Clonmacnoise was plundered by the men of Munster with the Vikings of Limerick ("Foreigners of Luimnech") 953 AD.
- [Annals of Inisfallen 963 AD] Death of Donnchad, son of Ceallachan, also a king of Cashel. The O'Donovan pedigree goes back to Callaghan, a 10th-century King of Munster. Another O'Donovan family of Kilkenny who claimed descent from Eoghan, a 3rd-century King of Munster, produced one of the most celebrated historians, John O'Donovan.
- Clanna Rory of Ulster