General Notes

Conn Cead-Cathach was the son of Fedhlimidh Rachtmar, the High King of Ireland and Ughna, daughter of the King of Lochlin (Denmark). Conn is also known as Conn of the 100 Battles or the 100 Treaties. His grandfather was Tuathal Teachtmar, the Irish High King who made Connacht the Supreme province of the five in Ireland at the time.
Conn's name is unusual and according to legend, portions were given late in life or after his death. Conn Cead-Cathach means Conn (speed, virtue, champion), Cead (one hundred) and Cathach (of Battles). Conn also had an older meaning that is referred to as dog, or a warrior with the fighting qualities of a dog.
Little is known of Conn's youth and he did not succeed his father in rule. Between Fedhlimidh and Conn ruled Cathair Mor. Cathair was defeated in a great battle by Conn in Meath. He then took the reigns as Ard-Righ or High King.
During Conn's lifetime he certainly lived up to his name, fighting numerous battles most of which were against Mogh Nuadat of Munster.
The Ithians and Eberians alternately ruled the province of Munster in an arrangement that worked peacefully until the Earnaan arrived. The Earnaan had been forced out of Ulster and applied for land in Munster to King Duach who gracefully assented. But the Earnaan did not repay their host's kindness and instead, took control of the province. The Eberians revolted and attempted to regain their territory. Conn, the High King, sent aid to the Earnaan but even with his help they lost the battle.
The Eberian King Mogh Nuadat then sallied forth against Conn himself to address Eberian grievances, but he was defeated and forced to retreat to Spain. There he married Beara, daughter of Heber Mor, King of Castile. Later, with the Castillian King's support Mogh Nuadat returned to Ireland with 2,000 troops under the command of Fraech, the King's son, to claim the throne. Conn and his allies fought valiantly, but after 10 battles were forced to relinquish one half (the southern half) of Ireland to Mogh Nuadat.
But Mogh Nuadat was not satisfied and soon ventured north against Conn again. This time, Conn attacked the enemy army at night hoping for surprise. All with him joined in the attack except for the forces of Goll MacMorna, who had vowed never to attack an enemy by surprise. The attack took place and was on the point of failing when the sun rose and Goll's forces joined the fray. Fresh and unhindered by the darkness they turned the tide of the battle and defeated Mogh's forces. In the process Mogh Nuadat and Fraech, the Castillian King's son, were killed.
After the battle Conn gave one of his daughters to his ally in marriage and another to the son of Mogh Nuadat thus permanently linking the Ithians, Eberians, Deagades and his own people, the Eremonians, through family alliances. For his crime of the night attack and the unfair slaying of Mogh, Conn was forced by the High Judges to pay a fine of his own jewelry, sword and shield, as well as 200 each of steeds, chariots, ships, spears, swords, cows, and slaves. Although the price was high, Conn was alive and still High King.
As his name implies, Conn faced many more battles in his lifetime. He is also rumoured to have a hand in the colonization of Scottish Dalriada or Scotia Minor. He was finally killed at Tara in approximately 157 AD when the King of Ulster sent 50 robbers dressed as women to dispatch the monarch. Conn's son Conaire II then took the reins as High King of Ireland.