From A Wiki of Ice and Fire
The Hornfoot, sometimes called Hornfoots, are a tribe of free folk beyond the Wall who are known in the Seven Kingdoms through tales. They wear nothing on their feet, which turns the soles of their feet hard.
The Hornfoot people warred with the Nightrunners before Mance Rayder negotiated a peace between them.
A Storm of Swords
The Hornfoot men join with Mance Rayder for his attack on the Wall.
A Dance with Dragons
Two clan chiefs of the Hornfoot kneel to Stannis Baratheon at the Wall.
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