Styr Magnar

Styr is the Magnar of Thenn and leader of the Thenns, a tribe of free folk. He rules with an iron fist and commands absolute loyalty from his men. Mance Rayder had to defeat Styr three times before the Magnar agreed to support him as King-beyond-the-Wall.

Please see the following links for more info:

https://awoiaf.westeros.org/index.php/Styr

https://gameofthrones.fandom.com/wiki/Styr