This story comes from the end of the 18th century, but seems to hark back to an earlier time. However it is likely that the Viking element was grafted on later – did Vikings pick up local pilots? And potatoes didn’t arrive in the islands until the middle of the 18th century, and even by the 1790s there was a resistance to growing them. However:
Some Uig men were out fishing around the Flannan Isles, and a Viking longboat came along and asked for a local person to guide them through the treacherous Sound of Harris. Murchadh Ban was chosen to go and be their pilot. He was married in Crowlista and all were anxiously awaiting his safe return to the village. However he didn’t return that year to Crowlista and thinking that some ill had befallen him, his wife assumed the status of a widow in the village. Two years after his departure, a foreigner dressed in strange clothes appeared in Uig. He walked past Murchadh Ban’s mother, who was breaking down manure with her hands in the potato plot, and remarked to her: “Haven’t you the filthy job?”
This was Murchadh Ban returning and his mother didn’t even recognise him. The longboat was hit by a gale when it reached the Sound of Harris and the Vikings were so wary of the area that they turned into deeper water and eventually returned to Gothenburg, where Murchadh Ban stayed for two years before he could obtain passage back to Lewis. It is said of him that once he returned that he wouldn’t eat any kind of fish because he was so sick of eating dried fish on the longboat, or because the fish in Gothenburg had not been as good as that in Lewis.