Venkoji Bhonsle (Marathi: व्यंकोजी/एकोजी १) (born 1629) or Ekoji I Bhonsle was the younger half-brother of Shivaji and founder of Maratha rule in Thanjavur. He was the progenitor of the junior branch of the Bhonsle family which ruled Thanjavur until the formal annexation of the kingdom by the British in 1855.
Venkoji was the younger son of Shahji Bhonsle, a military commander in service of the Sultan of Bijapur through his younger wife Tukabai Mohite. He succeeded to the jagir of Bangalore on the death of his father while his illustrious elder brother had carved an empire of his own.
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The Marathi inscriptions of the Thanjavur temple dates the capture of Thanjavur to January 1676. The Madras Tamil manuscript assigns the dates 1675 and 1679 to the conquest and end of Ekoji I's reign respectively.
Likewise, the Marathi inscriptions assigns Ekoji's death to 1684. However, Wilkes asserts that Ekoji was well alive in 1686-1687. The records of the British East India Company mention a king called Ekoji as late as 1699-1700.
However, Dharmakuta a commentary on the Ramayana suggests that Ekoji might have abdicated in the year 1684 in favor of his son Shahuji. However, it is quite unclear as to how many years he lived after the event.
In 1676-1677 Chattrapathi Shivaji made an expedition to the Carnatic to claim his portion of the jagir of Bangalore. Shivaji also desired to bring the whole of South India under Maratha rule. With this aim in mind, he made a treaty with Golconda, took Gingee and proceeded to Thanjavur after conquering all the lands north of the Coleroon river. But a Mughal Empire invasion forced him to turn back. He placed Vellore under the rule of a half-brother named Santoji. Ekoji I reacted by launching regular military campaigns into Santoji's territory with the intention of driving him away. However, in 1680, Bijapur succumbed to the invasions of Shivaji and handed over the administration of all lands to the north of the Coleroon river to Shivaji. Ekoji I was forced to become a vassal of Shivaji and pay him tribute. On the death of Shivaji, however, the tribute was stopped and Thanjavur retained its independent existence.