According to this website on the “Origin and meaning of the Hardings – the “Tough Guys” the surname Harding was (and is still) used in Scandanavia ‘to represent a “tough guy”‘
There was a King Harding of Hardanger in the 10th Century who was captured by the English. He was rescued by the Vikings who:
equipped a Viking ship, called Hardinggeita (lit. “The Harding ship”) to set sail to England and set their King free. The Hardings painted one side of the ship white and the other side black. When they approached the English shore they did so with the white side facing towards the shore…
… after which they managed to get to the prison tower and switched the king with an old man dressed like the king. Then they set sail and made their escape but with the black side of the ship facing the shore…
The English did not recognize them as the invaders as they were looking for a white ship. The saga ends with King Harding returning safely to Kinsarvik, Hardanger.
Other famous Hardings have included: