More specifically, were the monks of Lindisfarne aware of their existence, or were the attackers completely unknown and alien? The same question goes for the Viking’s mini excursion into Wessex in 789 and how it effected the local community there.
All I can find online is that this raid was the beginning of the ‘Viking Age’, but nothing to suggests activity, trade or other contact before this date. It seems improbable to me that there wouldn’t be any knowledge of them, especially considering the existing networks of trade, religion and communication at this time.
Conversely, how much knowledge did the Vikings and the wider Scandinavian peoples have of Europe? They must’ve known where Lindisfarne was and the wealth held there in advance. Did they have maps of the English coast/wider Europe?
Thank you in advance.
While more can always be said, I hope some of my previous answer might satisfy OP's curiosity:
+++
As for the British knowledge of Scandinavia, I suppose /u/textandtrowel's post in: In the new video game Assassins Creed Valhalla, a group of Vikings arrive in England in 873 AD and are immediately able to communicate with the locals. Would Vikings conducting raids and English of that time have be able to communicate? would be the most interesting to you, however.