At the end of 8th century Scandinavian cities became too populated and this led to the new wave of Europe expantion. The Vikings started to sail to the British Isles and attacked England in 793 AD.
In two years Vikings came to Ireland. Around 795AD they arrived to Raithlin Island, Antrim and Lambay Island, Dublin. They didn't spend any time and destroyed monastries at Iona, Inisbofin and Inismurray in the same year.
Notwithstanding the often raids Vikings never stayed in Ireland for a long time. They didn't organize army for this - Viking came with small independent groups, raid the new land quickly and disappear in the sea. The history shows, Viking didn't go deeper that 20 miles inland, they preffered to hit coastal targets.
It was good strategy that brought success but anyway some groups of Vikings did suffer defeats. In 811 AD the Ulaid obliterated Viking invaders. In 812 AD Locha Leinand, the King of Eoganacht and the men of Umail also won fights. But this didn't stop Vikings, they became bolder in their attacks and raided the city of Armagh three times in 832AD.
Viking Settlements
That’s how vikings set foot on the land of Ireland. In 840AD and 841AD they created first settlements at Lough Neagh. With time they refused the raid tactics and started to sail to Ireland in order to arrange life there. They founded other colonies at Cork, Dublin (Dubhilnn) and Waterford (Vadrefjord).
Vikings raided monasteries and murdered the inhabitants but their behaviour wasn’t too much different to that of native Irish tribes. Historical writings say that the Vikings and Irish could cooperate. By 844AD, the Vikings had founded a base at Lough Ree. From that point they could swiftly attack the nearby countryside. But even these raids were not without incidents. According to the annals, Turgesius (Viking leader), was drowned by Mael Sechnaill, king of the Ui Neill.
The Vikings' Mistake
But establishing a foothold in Ireland was a mistake of the Vikings. They became more vulnerable. Now Irish kings knew where they could find them. Vikings weren’t the envisible enemy anymore. Thus, the Viking settlement at Cork was completely destroyed and Mael Sechnaill attacked and pillaged Dublin in 849AD.
From the other side, Danish warriors attacked Ireland. They also threatened the Viking settlements. Vikings didn’t had another choice but to create alliances with Irish tribes. The situation became more ominous when in 860AD was destroyed Waterford, in 866AD all Vikings’ longports at the North of Ireland were burnt and in 902AD Cerball mac Muirecain of Leinster and Mael Finnia mac Flannacain of Brega joined together to make the Vikings leave Dublin.
Second Viking Age
The Vikings had to leave Ireland but they didn’t stop to sail the Irish sea and in 914AD they returned to Waterford Harbour. Less than for one decade thay renewed the settlements in Cork, Waterford, Dublin, Limerick and Wexford. They tried to expand their territories but numerous and more powerful Irish tribes didn’t allow to do this.
At the end of 10th century, one of the Vikings’ leaders Brian Boru became the great leader and in 1002AD he was the the High King of Ireland. But in 1014AD, in the Battle of Clontarf, he was killed. This time is considered to be the end of the Viking wars.
Conclusion
Since that time Viking page in the history of Ireland was closed forever but that period of time influenced the life of Irish. The Vikings made an indelible mark on Irish history by establishing towns at Dublin, Cork and Waterford. Vikings developed in the creation of weaponry, jewellery, ship building as well as the development of new battle tactics. Many of them adopted Christianity and intermarriaged with native inhabitans. As the result, the Vikings that remained in Ireland became assimilated into Irish culture while the Norse culture became the part of Irish life.