Around the time of Mahipala’s death in around 1043 AD, a vassal of the Palas named Hemanta Sen founded the Sena Dynasty.
This Dynasty appeared in 11th century and disappeared in 12th century.
However, independent rule of Senas in Bengal was established in his son Vijayasena’s time.
Vijayasena (1097-1160) is called as real founder of the Sena Dynasty. He was able to snatch away parts of Rarh region of Bengal from the Palas and some parts of Gauda Kingdom from the Assam regions.
His son Ballala Sena (1160-1178) introduced the social reforms in Bengal known as Kulinism.
Ballalsena was succeeded by Lakshamanasena.
Most of the history of the Sena Kings has been corroborated from the Copper Plates. They struggled with Palas, Gauda and their struggles were confined in Bengal, Assam and parts of Orissa. In 12th century, their territories were won by a Deva dynasty. The Deva dynasty was finally swept away by the invasion of Bakhtiyar Khilji and later we find the Mamluk Dynasty of the Slave Kingdoms as rulers of Bengal and Bihar.