The Luso–Maratha War of 1729–1732 was an armed conflict between the Portuguese Empire and the Maratha Confederacy, who invaded Portuguese territory in India.

Context
After a war against the Marathas, the Portuguese viceroy of Goa João Saldanha da Gama had previously signed with the Maratha Confederacy a peace treaty in 1726, which resulted in the "peace of Bassein", which would prove to be brief.

Despite the peace treaty, in May 1729, Maratha forces under the command of Pilaji Jadhavrao raided two villages in the vicinity of the Portuguese fortified city of Daman. Since the Marathas often excused their raids as the work of brigands, the commander of Portuguese forces in the region, general Francisco da Guerra de Mesquita, was instructed by the viceroy to conduct limited retaliatory attacks against the border Maratha towns from which such raids had come from. 

The Marathas took Portuguese retaliation of their raids as a sign that the peace treaty had been broken. By the end of May 1730, the Marathas invaded the region around Bassein and war spread across the region. The Marathas had never attacked Portuguese territory in so much force after the reign of Sambhaji.

Course of hostilities

In spite of Maratha numerical superiority, lack of internal unity made military operations difficult, and the Portuguese viceroy was approached with a peace offer through the English East India Company governor Robert Cowan in Bombay. The viceroy proposed to return captured Maratha belongings, however he refused to sign a peace while Portuguese territory was occupied by Maratha forces while the Marathas refused to return captured spoils or make peace unless the Portuguese paid tribute and allowed Hindu temples to be built on their territory.

Realizing that the Marathas would not make peace unless directly threatened, the viceroy dispatched reinforcements from Goa were to general Guerra de Mesquita, along with instructions to persistently raid Maratha territory and also engage in psychological warfare by threatening to forcibly baptize hindu prisoners, which in the words of the viceroy, "they resent much" though the general was forbidden from actually carrying out this task. In October 28 1730 Bagi Rao wrote to the British governor in Bombay stating: "The dispute between us and the Portuguese over Galiana-Biundi is notorious, and we have been conquering and will conquer their territories."

The British aided the Portuguese in 1730 with 200 musketeers, of which 50 were Europeans and 150 sepoys, 250 sepoys and 6 galliots.

By then, the shortage of fodder in the region threatened to bring Maratha cavalry incursions to a halt. Although numerically inferior, the Portuguese prevented the Marathas from taking advantage of their numerical superiority by engaging in vigorous offensive warfare with a mobile army, which pinned the Marathas. In April 3 1731 the viceroy decreed a general conscription for all Portuguese except those charged with Lèse-majesté. After reinforcements had arrived in Bassein, through persistent Portuguese attacks, Maratha offensive operations ceased. 

Successful Portuguese operations brought the Marathas to the negotiating table. During negotiations however, in mid June Pilaji Jadhavrao captured a Portuguese fort in Cambá without firing a shot, by convincing its garrison  to hand it over. It appears the Portuguese commander Luís de Melo de Sampaio was invited for talks under the guise of a truce and then held hostage until the fort was evacuated. The viceroy later criticized Melo de Sampaio for having failed the established custom of requesting hostages from the Marathas before talks, which would have uncovered the ruse. As a result of the treachery, the Portuguese called off peace negotiations, arrested the Maratha ambassador along with his family and attendants and hostilites continued. 

Persistent Maratha offers for peace in exchange for tribute, without withdrawing from Portuguese territory, were refused. The Marathas threatened to invade Goa, capital of Portuguese India, however this failed to intimidate the viceroy. At the same time, the Portuguese sought to convince the Mughals to attack the Marathas. Local Indian lords proved unreliable in their support for either side, inconsistently favouring whoever appeared to have the military advantage or initiative.

Treaty of Bombay 1732 and peace

By January 1732, the Marathas had been immobilized for six months, unable to effectively combat the Portuguese due to internal civil affairs in their territories beyond the Konkan, and a Mughal army under the command of Quiliscan was fast approaching. Many Marathas had begun to seek refuge in Portuguese territory from the advancing Mughals. The Portuguese had secretly promised aid to the Mughals against the Marathas.

Under the mediation of the British governor in Bombay, in January 30 a peace treaty was signed in Bombay Castle between the Portuguese, represented by Francisco de Melo de Castro and the Marathas, represented by Siva Rama Pandit and Raiagi Ramagi.

Aftermath
The Marathas withdrew from Portuguese territory. Nevertheless, Bajirao planned to resume hostilities against the Portuguese with an attack on Salcette Island on 13 March 1733. Peace would prove to be short, as five years later the Marathas would again invade Portuguese territory and attack Bassein.

List of Conflicts

See also
Maratha–Portuguese War (1683–1684)
Portuguese India
Mughal-Maratha Wars
Battle of Vasai

References

Conflicts in India
Conflicts in 1729
Portuguese India
Colonial India
History of Portugal
 History of Goa
 History of Mumbai
 History of Vasai
 History of Daman and Diu
 Wars involving Portugal
Wars involving the Maratha Empire