From villains.fandom.com:

In an alternate reality, Batman became a ruthless anarchist after his parents are gunned down by Stalin's police force, vowing revenge on Pyotr Roslov and 20 years later became the most wanted man in the Soviet Union.

From wikipedia we learn that Pyotr Roslov was the head of the NKVD. He shoots a dissident couple (batman's parents) in front of their son (who would later become Batman) for anti-Superman propaganda.

From villains.fandom.com:

In an alternate reality, Batman became a ruthless anarchist after his parents are gunned down by Stalin's police force, vowing revenge on Pyotr Roslov and 20 years later became the most wanted man in the Soviet Union.

From wikipedia we learn that Pyotr Roslov was the head of the NKVD. He shoots a dissident couple (batman's parents) in front of their son (who would later become Batman) for anti-Superman propaganda.

This version of Batman is an adaptation of the character that appears in the DC comic book Superman: Red Son Vol 1 1.

From villains.fandom.com:

In an alternate reality, Batman became a ruthless anarchist after his parents are gunned down by Stalin's police force, vowing revenge on Pyotr Roslov and 20 years later became the most wanted man in the Soviet Union.

His parents in this universe were dissidents.

From villains.fandom.com:

In an alternate reality, Batman became a ruthless anarchist after his parents are gunned down by Stalin's police force, vowing revenge on Pyotr Roslov and 20 years later became the most wanted man in the Soviet Union.

From wikipedia we learn that Pyotr Roslov was the head of the NKVD. He shoots a dissident couple (batman's parents) in front of their son (who would later become Batman) for anti-Superman propaganda.