Such was Pulakeshin’s efficiency in guarding the passes of the Narmada that Harsha was compelled to accept the river as the demarcation and retire from the battlefield.

Researchers from the Bhandarkar Oriental Research Institute (BORI), which houses South Asia’s largest collection of manuscripts and rare texts, claim to have fixed the date of Emperor Harshavardhan’s defeat to the Chalukya King Pulakeshin II by decoding a copper plate.

The date of Pulakeshi’s great triumph over Harsha in a battle fought primarily with elephants, on the banks of the Narmada, can now be fixed at 618 AD, said Shreenand Bapat, Registrar, BORI.

Pulakeshin, who ruled from the Chalukyan capital of Badami, challenged Harsha’s conquests. The former had established himself as ‘lord paramount’ of the south, as Harsha had of the north. Unwilling to tolerate the existence of a powerful rival in the south, Harsha had marched from Kanauj with a huge force. Such was Pulakeshin’s efficiency in guarding the passes of the Narmada that Harsha was compelled to accept the river as the demarcation and retire from the battlefield after losing most of his elephant force.

“It was believed that the battle occurred sometime between 612 AD and 634 AD. But now, thanks to this new copper plate, it can be ascertained definitively to have taken place in the winter of 618-619 AD,” Dr Bapat said, remarking that the copper plate was received by the BORI from Raghuvir Pai, a noted coin-collector of Mumbai.

Interestingly, in Volume II of the classic nine-volume History of India series (published in 1906 and edited by American historian-linguist AV Wiliams Jackson), the great British Indologist and historian Vincent A Smith, with astonishing accuracy, places the date of the battle at around 620 AD. The plate is also useful in fixing the details of the coronation of Pulakeshi II in 610-611 AD, said researchers. Pulakeshin anointed himself king after defeating his uncle, Mangalesha. Legend has it that Mangalesha, the regent, wanted to deny his nephew the Chalukya throne. The plate further records the grant of 50 ‘ nivarthanas’ (a unit of land) by Pulakeshin from the village Brahmana-Vataviya (in modern-day Paithan Taluka of Aurangabad) to a Vedic scholar, Nagasharma.

This donation must have been made by the Chalukya king during his return from the Narmada campaign against Harsha, scholars said.