One of the things about the dark ages is the lack of documentation about what happened. TBH pretty much why its called the Dark Ages. However there was some stuff written down and in particular the settlement of Wirral by Norsemen who had been recently evicted from Dublin and who had been beaten back by the Welsh when they decided Ynys Mon looked like a nice place to go. The document in question is called the three fragments and it tallies with other Saxon chronicles of the time. So what we have is actual documented information of the migration. Prior to the stuff in the 3 fragments btw is that Ingimund left Norway after Harald Hárfagri (the nice haired) unified Norway and several smaller Norse Kings decided their life expectancy was going to go down the toilet.
A transcription of the 3 fragments reads as follows
Transcribed by Gavin Chappell
Through the fasting and prayers of the holy man Celé Dubhgaill, Ingimund and his Norsemen were forced from Dublin and fled overseas to Britain. Here the men of Anarawd ap Rhodri marched against them, and they fought a hard battle on Anglesey. In the end, Anarawd drove Ingimund’s men from the British lands. Sailing up the coast, they beached in northern Mercia, and contacted Aethelflaed, Lady of the Mercians, whose husband Ethelred was in a disease. Ingimund asked lands of the Lady in which he could settle, for at that time he was weary of war, and Aethelflaed gave him lands near Chester. Ingimund stayed peacefully there for four winters, but when he saw the city of Chester full of wealth, and the choice land around it, he wanted to possess them.
Afterward Ingimund came to the Norsemen, making a great complaint in their presence. He said that they were not well off without good lands, and that it was right for them all to seize Chester and to possess it with its wealth and its lands. Many great battles and wars arose on account of that. This is what he said. ‘Let us beseech them and implore them first, and if we do not get them willingly in this way, let us contest them by force.’ All the leaders of the Norsemen agreed to this. Ingimund then came to his house with an assembly following him. Though they made this a secret, the Lady of the Mercians came to know of it. Therefore the Lady collected large forces around her in every direction, and the city of Chester was filled with her hosts. The armies of the Norsemen assembled towards Chester and, since they did not get what they wanted by beseeching or supplication, they proclaimed battle on a certain day.
On that day they came to attack the city; there was a large force with many freemen in the city awaiting them. When the forces who were in the city saw, from the wall, the great armies of the Norse approaching them, they sent messengers to the ailing earl of Mercia, to ask his advice and that of Aethelflaed. This was the advice they gave: to make battle near the burg outside, and the gate of the city should be wide open, and to choose a body of horsemen, concealed on the inside, and those of the people of the city who would be strongest in the battle should flee back into the city as if in defeat, and when the greater number of the forces of the Norse came inside the gate of the city the force hidden yonder should close the gate after this band and not admit any more: capture those whom came into the city and kill them all. This was all done accordingly, and they thus made complete slaughter of the Danes and the Norse.
Great, however, as was that slaughter, the Norsemen did not abandon the city, for they were stubborn and vicious, but they all said that they would make many hurdles, and put posts under them, and pierce the wall under them. They did not delay this; they made the hurdles, and the forces were under them to pierce the wall, for they were eager to take the city to avenge their people.
Then Ethelred and Lady Aethelflaed sent messengers to the Irishmen who were among the host [a reference to the Gall-Gaedhil, or Gaddgedlar; Irish who were fostered with Norse families, and normally had a reputation for being even worse enemies of the Church than the rest of the Vikings – they seem to have had an attack of Catholic guilt at this point] to say to them, ‘Life and health to you from Ethelred and Aethelflaed, who have all authority over the Mercians, and are certain that you are true and trusty friends to them. Therefore, you should take their side; for they did not bestow greater honour on any Mercian warrior or cleric than they gave to each warrior and cleric who came to them from Ireland, because this inimical race of pagans is equally hostile to you also. It is right then, that as you are trusty friends, for you to help them on this occasion.’
This was the same as if it were said to them; We have come from faithful friends of yours to address you so that you asked the Norsemen what tokens of lands and treasures they would give to those who would betray the city to them. if they accept this, to bring them to swear to a place where killing them will be easy; and when they will be swearing by their swords and by their shields, as is their custom, they will lay aside all their missile weapons. They all did accordingly, and they put away their arms. And the reason the Irishmen did this to the Danes was because they were less friends to them than to the Norsemen. They killed many of them in this manner for they threw rocks and large beams down upon them; great numbers also were killed by darts and spears and by every other means for killing man.
But the other forces, the Norsemen, were under hurdles piercing the walls. What the Mercians and the Irish who were among them did was to throw large rocks so that they destroyed the hurdles over them. What they did in the face of this was to place large posts under the hurdles. What the Mercians did was to put all the ale and water of the town in the cauldrons of the town, to boil them and pour them over those who were under the hurdles so that the skins were stripped from them. The answer that the Norsemen gave to this was to spread hides on the hurdles. What the Mercians did was to let loose on the attacking force all the beehives in the town, so that they could not move their legs of hands from the great number of bees stinging them. Afterwards they left the city and abandoned it. It was not long before they returned.
So to summarise. Ingimund left Norway, settled in Dublin (a big trading port) got kicked out of Dublin and tried to settle in N Wales. The Welsh drove him off and he ended up on the Wirral. Whether Aethelflaed actually gave them the land or if they settled first and she then thought they would act as a good deterrent against other Norse/Dane attacks is something i am unsure on. People who have done actual research though seem to agree that she let them settle so I will go with that for now.
Ingimund decided Chester looked like a nice place to “visit” and was beaten back and if you believe the folklore the defenders won by throwing beehives at the vikings after getting the Irish to switch sides. Chester was refortified by Aethelflaed in 907 and became a major trading hub between York, Dublin and other places. Meols was also an important trading port and having the Norse on the Wirral probably helped trade via that route. What happened to Ingimund after 907 is unsure but it is known that there was an enclave of viking traders in the south of Chester for many years afterwards. The Vikings maintained a presence on Wirral until the Ravaging of the North by William the Bastard (AKA William the Conqueror) in 1069/70. The Hiberno-Norse community stood up to William who in turn crushed them.
If you are interested in the wider picture of the Vikings on Wirral there is a great book by Stephen Harding you should read – Viking Mersey (ISBN-10: 1901231348 ISBN-13: 978-1901231342)