Tarrlok was the last representative for the Northern Water Tribe on the United Republic Council and also served as its chairman.
He was an ambitious politician, considered fair-minded and likable by the general public; however, behind closed doors, he was a manipulative man who held a long-standing rivalry with Councilman Tenzin.
Tarrlok sought to fight the Anti-bending Revolution with violence rather than peaceful negotiation.
He was willing to go to extreme lengths to win the conflict against the Equalists, even if it meant fanning the flames of aggression and risking the lives of innocent people. After the Equalists seized control of Republic City, Tarrlok revealed to Korra and Mako that he was the younger brother of Amon, the leader of said group, and that together they shared a tragic past.
After learning the danger Amon really posed, the United Republic Council held a meeting, during which Tarrlok proposed to assemble a task force whose sole mission would be "to fight Amon and bring him to justice".
Tenzin immediately dismissed this idea, asserting that such an aggressive strategy would only worsen the relations between benders and nonbenders, and he claimed it was merely a ploy to grant Tarrlok more power.
However, as he grew older, Tarrlok and his brother discovered they were waterbenders, and Yakone commenced their brutal training.
Much to his father's frustration, Tarrlok was not a prodigy like his brother, and thus was frequently the subject of Yakone's outbursts of rage.
At the age of seven, Tarrlok, along with Noatak, left on a supposed hunting trip with their father, far away from their home, during which Yakone revealed his true identity as the notorious former crime boss of Republic City and a once powerful bloodbender.
Tarrlok eventually moved to Republic City, and, having learned from his criminal father's mistakes, he ascended through the government, eventually becoming the Northern Water Tribe representative in the United Republic Council and the chairman of said council.
Tarrlok managed to conceal the truth about his parentage and, through charismatic politics coupled with a fierce stance against the Equalists, maneuvered himself in position to be Republic City's "savior".