[1] He was only son and youngest child of Jayappa Rao Scindia, and ascended to the throne of Gwalior on the death of his father on 25 July 1755.

As he was only 10 years of age at that time, a regency was established, led by his uncle Dattaji Rao Shinde, Jayappaji's brother, which lasted until 10 January 1760 when Dattaji was killed and defeated in Battle of Barari Ghat.

Jankoji with around 7,000 troops was positioned to the right of Shamsher Bahadur and was opposed to Najib Khan Rohilla.

Kashiraj met Jankoji secretly in a tent of Barkhurdar Khan, he was wounded with a ball and with a spear in the arm.

Kashiraj was told by Moti Lal, the Diwan of Barkhurdar Khan that Jankoji would be released if a ransom of seven lakhs would be paid.