Bane breaking Batman's back is one of the most iconic moments in comic book history. This pivotal event occurs in Batman #497, published in July 1993 as part of the famous Knightfall storyline by DC Comics.
What Happened:
In the Knightfall arc, Bane orchestrates a master plan to mentally and physically break Batman. He begins by freeing all of the inmates from Arkham Asylum, including the Joker, Scarecrow, Poison Ivy, and others. Batman is forced to exhaust himself over several days recapturing them all, running on little rest or recovery.
Once Batman is completely worn down, Bane finally confronts him in the Batcave itself, having deduced Batman’s secret identity as Bruce Wayne. The exhausted and weakened Batman puts up a fight but is clearly no match for the fresh and powerful Bane.
In a brutal showdown, Bane lifts Batman above his head and smashes him down over his knee, breaking his back. This image became legendary and is often referred to as "The Breaking of the Bat."