He was a remarkable little man, but so swift of foot that no horse could overtake him.

There was a man from the Uplands called Fin the Little, and some said of him that he was of Finnish race. He was a remarkable little man, but so swift of foot that no horse could overtake him. He was a particularly well-excercised runner with snow-shoes, and shooter with the bow. He had long been in the service of King Hrorek, and often employed in errands of trust. He knew the roads in all the Upland hills, and was well known to all the great people. Now when King Hrorek was set under guards on the journey Fin would often slip in among the men of the guard, and followed, in general, with the lads and serving-men; but as often as he could he waited upon Hrorek, and entered into conversation with him. The king, however, only spoke a word or two with him at a time, to prevent suspicion. In spring, when they came a little way beyond Viken, Fin disappeared from the army for some days, but came back, and stayed with them a while. This happened often, without anyone observing it particularly; for there were many such hangers-on with the army.

Heimskringla by Snorri Sturluson