Darguun

Wild goblin tribes have plagued the eastern badlands of what used to be Breland for as long as humans have inhabited Khorvaire. Driven there by the human expansion the tribes were too busy warring with each other to pay attention to the wider world, and the humans left them to slaughter themselves.
Just before the Great War, House Deneith established a relationship with the goblinoids whose warlike ways made them excellent mercenaries. It quickly became popular for the wealthy to employ goblin bodyguards. Soon afterward, the Great War began, and it was only a small step for House Deneith to provide goblinoid troops where it had before provided exotic security forces. Goblinoid mercenaries eventually supplemented several nations' armies, which relied heavily on such soldiers as the war dragged on. That dependence proved catastrophic. Seventy-five years into the war, a shrewd goblin warlord named Haruuc, who had spent his youth as mercenary and adventurer, secretly united goblinoid warlords and chieftains to his cause, and then turned on his employers. Haruuc's forces carved a massive chunk of land from the borderlands, killing many of the people they had been contracted to protect. Dubbing the territory Darguun, Haruuc became the Lhesh Haruuc Shaarat'kor—High Warlord Haruuc of the Scarlet Blade.
As Haruuc calculated, none of the kingdoms from which he carved Darguun could commit military forces to reclaim the land. Breland's king quickly made terms with Lhesh Haruuc, recognizing the land of Darguun in exchange for an alliance. When the treaty to end the war was crafted, most nations recognized Darguun as a state unto itself. For his part, Lhesh Haruuc vowed to be at peace with the nations that recognized Darguun—a promise managed to keep. 
After the war's end the goblin have lost their common enemy and old feuds were rekindling. The young country was constantly on the precipice of reverting back to tribal warfare, held together only by the will of Haruuc himself who was in the twilight of his life with no identified heir to the throne. In Haruuc's final act of genius that saved his country from collapse, the hobgoblin warlord introduced the goblin tribes to martial arts, providing an outlet for their warlike nature while instilling discipline in his people. In the final year of his life he held a tournament to decide the next Lhesh, which the goblinoids found acceptable to outright war, and so the succession of Lheshes is decided through a contest of martial arts. 
Each goblin tribe has it's own martial art which they hone and develop, occasionally young prodigies are sent on a pilgrimage of the world to bring back new techniques so that their champion may take the title of Lhesh at the next tournament.