What kinds of people take up the calling of barbarian in the Federated Nations? How do they fit into the world?

Barbarians are those who connect with the ambient anima through their emotions and channel that power through their bodies to affect the world around them. This emotional connection is often called "Rage"--anger is one of the easiest ways to tap into wellspring. It's not the only way, and many consider themselves tapping into the power of the elements, of natural spirits, or of their ancestors. They all rage, just in different way and to different effects. Raging stirs volcanic emotions within the barbarian--even those barbarians who have learned to cast spells cannot do so while raging (and cannot concentrate on spells while raging, even if those were cast earlier) because of this internal roil of passion.

Barbarian Organizations and Training

Barbarians who choose the Path of the Battlerager are usually chosen and trained for that from early years by their community leaders. Zealots are chosen from the ranks of the faithful, usually of one of the more militant deities. Ancestral Guardians and Totem Warriors learn at the level of tribes, mostly. Storm Heralds and Berserkers are self-made and alternately treasured and feared for their destructive powers.

Barbarians in the Council Lands

Barbarians are an oddity in the Council Lands, despite being found among most races. While half-orcs are the stereotypical Berserkers, there are many stout halflings that have exhibited such powers. Dwarves tend to the Battlerager or Ancestral Guardian paths. Humans, tieflings, and aasimar are the predominant Zealots; wood elves take the Totem Warrior and Ancestral Guardian paths quite frequently. Storm Heralds come from all races, although high elves are rarely barbarians at all.

Culturally, barbarians have mixed status. Their raw destructive power tends to be frowned on and watched carefully. On the other hand, citizens of the less settled lands rely on the strength and resilience of those of this calling.

Barbarians in the Stone Throne

Barbarians are rare among the people of the Stone Throne. When they arise, they are almost always self-taught and considered unreliable warriors. Zealots of the Queen Ascended are a partial exception--some people consider them goddess-touched and holy, although they are feared and used as shock troops by the ecclesiastical establishment. No race tends to produce more barbarians than any other.

Barbarians in Byssia

Barbarians are relatively common in Byssia, especially those of the Ancestral Guardian, Storm Herald, and Totem Warrior Paths. Wood elves tend to the latter two paths, whereas humans tend to the first two, although all three can be found among all the races native to this land. They have high status--the chief military officers of local militia tend to have rage-esque powers. 

Barbarians in the Remnant Dynasty

Barbarians are very common among the orcish population and not uncommon among the rest. Orcs tend to the Berserker path quite heavily, although Totem Warriors and Ancestral Guardians are well represented. Dragonborn (especially of Clan Anu) tend to the Battlerager or Zealot. While goblins are rarely barbarians, Hobgoblins tend to the Ancestral Guardian path and Bugbears to the Berserker path. Orcs claim Rage as their heritage--they claim to have been the first Berserkers. As such, barbarians have high status among them. Many of those that volunteer for service at the Wall are barbarians.