During the Revolt of 1857, different leaders led the uprising in various regions of India. Kunwar Singh led the rebellion in Arrah, Bihar, while Birjis Qadr, the son of Begum Hazrat Mahal, emerged as the prominent leader in Lucknow after his mother declared him the Nawab. Hence, the correct association is: Arrah (Bihar) : Kunwar Singh; Lucknow : Birjis Qadr.