Plot
After the conclusion of the War, Aang and Zuko brought people from the four nations together and founded the United Republic of Nations and its capital, Republic City, a large "metropolis powered by steampunk-type technology" such as cars and motorcycles.Aang and Katara had three children, the youngest of which was Tenzin, an airbender. Meanwhile, Toph Beifong traveled extensively to teach metalbending. After Aang's death, the next Avatar, Korra, was born in the Southern Water Tribe.
At the present time, seventy years after the end of the War, Korra is a rebellious seventeen year-old girl.As the Avatar, she has already mastered waterbending, earthbending, and firebending.
At the beginning of the series, Korra travels to Republic City and starts her airbending training with Tenzin.Tenzin himself is married to Pema.