The Get of Fenris (originally and sometimes still known as the Fenrir, or "Those of Fenris") trace their roots to Germanic tribes and wolf packs of Germania and Scandinavia. They are known as fierce and unforgiving warriors. The Get of Fenris prize strength in all forms, not only of body but also of mind. They constantly train in battle, duel, engage in survival activities to hone their warrior skills. Cult of strength and endurance is so prevailing that they prize every battle-scar and sometimes engage in ritual (self)mutilation to prove themselves. Once seen as elitist or even Nazi in temperament, the Fenrir are, in truth, one of the most meritocratic; any Garou who can prove themselves strong is considered worthy by the Get, regardless of their breeding. Those who are weak are worse than chaff, best lost in failed attempts to prove their strength.
The Fenrir are infamous for the constant "testing" to which they subject the other tribes of Garou. The Fenrir use these tests to determine the fitness of the other tribes in the task of defending Gaia and her Caerns. In practice, the Fenrir are known to challenge members of other tribes to duels and to take control of caerns, by force if necessary, if the rightful claimants are unable to defend them. It is for this reason (or pretext) that they have engaged in a series of battles with the Fianna tribe and were a primary force in the war with the Uktena and Wendigo tribes and their Native-American kinfolk.
They are also notorious for being unable to compromise and prone to rage - the reason they are derided by other tribes. Also, more manipulative tribes (like the Shadow Lords) tend to think of Fenrir as of cannon fodder.