By the 12th century, the Kingdom of Uladh belonged to Irish dynasty that dominated the northern territories of Ireland but by 1177 they would be overthrown by the invading Anglo-Normans.
The invasion of John de Courcy
During the Anglo-Normal invasion of 1171, John de Courcy arrived to help the King of Leinster to overthrow the High King of Ireland.
By 1175 the Treaty of Windsor was signed which granted the High King of Ireland to remain in his position as long as he and the other Irish Kings made an oath swearing loyalty to the King of England.
The land was divided up between the Irish kings and settling Anglo-Normans but the occupying force of the Normans wanted more.
The invasion of Ulster
One year after the signing of the Treaty of Windsor a large Norman army invaded Armagh in Ulster in an attempt to land grab. The Irish suppressed the attack killing over 500 Norman soldiers and with the help of the Kinel Owen the attacked the castle at Slane in Meath driving the Anglo-Normans out of Galtrim, Kells and Derrypatrick.
In 1177 John de Courcy set out with 22 knights and 300-foot soldiers to overthrow the Irish dynasties who controlled Ulster.
He first took over the Downpatrick without resistance and defeated the last King of Ulster. de Courcy went onto strengthen his position in Ulster by building fortifications and the castle at Carrickfergus.
The Earldom of Ulster
When John de Courcy invaded and took control of Ulster he did so without the permission of King Henry II.
By 1199 the son of Henry II, John, became the King of England and granted Hugh de Lacy permission to go to war against John de Courcy.
Hugh de Lacy captured John de Courcy in 1204 and a year later created the Earl of Ulster in what was de Courcy’s territory. Hugh de Lacy went onto capturing the remaining Kingdom of Ulaid.