Zuko's Uncle in Avatar: The Last Airbender and a former Fire Nation General. He was due to ascend to the throne until he abandoned the siege at Ba Tsing Tse because of the passing of his only son. He is a FireBending Master, fond of games and Tea, a member of the Order of the White Lotus, and has a habit of giving sage advice to all the right people at all the right times. Note that the voice actor changed between seasons two and three of Avatar: The Last Airbender.
"You Must look within yourself to find yourself, only then will your true self reveal itself"- Zuko mimicking Iroh
"Perfection and Power are overrated. I think you are very wise to choose happiness and love" - Iroh to Aang