After the death of
Madhavrao Peshwa in 1772, his brother
Narayanrao became
peshwa (prime minister) of the Maratha Empire. Narayanrao's palace guards murdered him in August 1773, and his uncle
Raghunathrao (Raghoba) became the Peshwa. However, Narayanrao's wife,
Gangabai, gave birth to a posthumous son, who was the legal heir to the throne. The newborn infant was named
'Sawai' Madhavrao (Sawai means "One and a Quarter"). Twelve Maratha chiefs, known as the Baarbhai and led by
Nana Phadnavis, directed an effort to install the infant as the new Peshwa and to rule in his name as
regents.
Raghunathrao, unwilling to give up his position of power, sought help from the
British at
Bombay and signed the
Treaty of Surat on 6 March 1775. According to the treaty, Raghunathrao ceded the territories of
Salsette and
Bassein (Vasai) to the British, along with part of the revenues from
Surat and
Bharuch districts. In return, the British promised to provide Raghunathrao with 2,500 soldiers. At the same time, the Marathas tried to form a military alliance with the French. Two Frenchmen, Saint-Lubin and M. Montigny acted as intermediaries between France and the Poona Regency. Although the alliance proposals went nowhere, British suspicions of a global anti-British front increased in the midst of the concurrent
American War of Independence. The
British Calcutta Council condemned the Treaty of Surat, sending Colonel Upton to
Pune to annul it and make a new treaty with the regency. The
Treaty of Purandhar (1 March 1776) annulled that of Surat, Raghunathrao was pensioned and his cause abandoned, but the revenues of Salsette and Bharuch districts were retained by the British. The Bombay government rejected this new treaty and gave refuge to Raghunathrao. In 1777, Nana Phadnavis violated his treaty with the Calcutta Council by granting the French a port on the West coast. The British retaliated by sending a force towards Pune. ==Initial stage and Treaty of Purandar (1774–1775)==