Prior to the events in "The Last Airbender", Iroh was the firstborn son of , but Azulon was succeeded by his second son, Ozai, following Iroh's retreat from public affairs after his son Lu Ten died in the siege of the Earth Kingdom's capital Ba Sing Se, which had held against numerous successive Fire Nation efforts at capture during the duration of the Hundred Year War. Iroh had a vision early in life that he would be the one to capture the city, but the death of his only son broke his desire to continue in the effort; having always been driven more by a sense of duty than personal ambition, Iroh abandoned the siege.