Bane is the main antagonist of The Dark Knight Rises, described as a mysterious and physically-imposing revolutionary militant excommunicated from the League of Shadows portraying himself as a "liberator of pain", who rises to dominant power from the criminal underworld by intending to continue Ra's al Ghul's legacy by finishing his work on destroying Gotham with a nuclear time bomb. His childhood friend is Ra's daughter Talia, and he uses his brute strength and wears a wrap-around respiratory mask to keep him alive and hide the injuries he suffered while in an ancient prison at a young age to add darkness to all of his terrible crimes and misdeeds.
History
Early Life
While very little information regarding Bane's early life before he turned to a life of crime was confirmed, he was luckily reported to have been born and raised in a centuries-old foreign penitentiary known as "the Pit", where he spent most of his life incarcerated as a prisoner learning the truth about despair. Although the officials of Gotham City were led to believe that he escaped the prison as a child, it was later revealed that he was actually the friend and protector of Talia al Ghul, a young girl ultimately revealed to have escaped, whose mother, the daughter of a local warlord, gave birth to in the Pit after being banished there by her father. When the mother was killed by the other inmates, Bane protected the girl until the latter finally escaped. He tried to hold the prisoners back during her climb out of the Pit, but they attacked and severely injured him. Despite attempts by the prison's doctor to heal his injuries, Bane was left in a state of constant pain until Talia returned with her father Ra's al Ghul, who massacred the prisoners in revenge for his wife's death and saved Bane by outfitting him with a mask providing a constant stream of analgesic gas which kept his pain "just below the threshold" before recruiting him and Talia into the League of Shadows. However, Ra's eventually excommunicated Bane or being a reminder of the prison his wife was left to die in and his platonic love for Talia.
Bane was brought back to the League shortly after Ra's died trying to carry out its mission to force Gotham to destroy its own corrupt infrastructure through mass panic, assuming control of the organization in his place.