Peshwa Madhav Rao II was Peshwa of the Maratha Empire in India, from his infancy. He was known as Sawai Madhav Rao or Madhav Rao Narayan. He was the posthumous son of Narayanrao Peshwa, murdered in 1773 on the orders of Raghunathrao. Madhavrao was considered the legal heir, and was installed as Peshwa by the Treaty of Salbai in 1782.
Madhavrao was the Posthumous son of Peshwa Narayanrao by his wife , Gangabai. After Narayanraos murder, Raghunathrao became Peshwa but was soon deposed by the courtiers and knights of the Maratha Empire. They instead installed Gangabais new born son, Madhavrao II, as the Peshwa with the courtiers themselves, led by Nana Fadnavis, as the Regents.He was made Peshawa when he was barelydays. His time in power was dominated by the political intrigues of Nana.
Source: Wikipedia