[4] A Buddhist Mahāyāna Text Mañjuśrī-Mūlakalpa records the existence of Gauda kingdom in Bengal before it was replaced by Gupta Empire in the 4th century.

[5] King Shashanka is often attributed with creating the first separate political entity in a unified Bengal called Gauda.

[2] The Chinese monk, Xuanzang (Hiuen Tsang) travelled from the country of Karnasubarna to a region in the present-day state of Orissa ruled by Shashanka.

Nagendranath Basu has argued that Shashanka was the son / descendant of Raja Karnadeva, who founded the city of Karnasubarna in Bengal.

[12] And that after the death of Mahasenagupta, Shashanka drove the later Guptas and other prominent nobles out of the region and established his own kingdom with his capital at Karnasubarna.

Other historians like Sailendra Nath Sen is of the opinion that Mahasenagupta - already under pressure from the Maukharis (for failing to provide adequate protection) - wouldn't have knowingly appointed Shashanka to such an important position.

Middleton (2015) argues in a similar vein that Shashanka served as maha samanta to a Gauda king, possibly Jayanaga.

[2] According to Jain writers of the thirteenth and fourteenth centuries, Gauda included Lakshmanavati in present-day Malda district.