The name of Tenzin is taken from Tenzin Gyatso, the fourteenth Dalai Lama, and means "Upholder of teachings." Tenzin is Korra's airbending teacher just as Gyatso was Aang's.
General Iroh, Zuko's grandson, who is named after Zuko's uncle, is voiced by the same voice actor who played Zuko in the original series, Dante Basco.
In the opening theme, it is the most recent Avatars who are seen performing their respective bending: Earth is by Kyoshi, Fire by Roku, Air by Aang, and Water is by the current Avatar, Korra.
The character of Mako was named after the original voice of Uncle Iroh in Avatar: The Last Airbender (2005-2008). Appropriately, Mako is a firebender.
The name of the masked Equalist leader, Amon, means "The hidden one."