How much did the Scandanavians and kingdoms in the British Isles know about each other before the Viking Age began?

by coaubry

Pretty much the title. I'm wondering if the first Norse raiders knew where they were going or if they kicked off the Viking Age by accident.

y_sengaku

While there will always be more to be done/ said, I wonder whether some links to relevant threads I posted before in: How much did the 'Vikings' really know about the West at the time of Ragnar Lothbrok? might satisfy OP's curiosity (Of course, I'm willing to answer/ find any additional relevant question/ clarification).