Great misfortune of our nation is that we are not aware of the real History
Parashara was the father of sage veda-vyasa. He was the orator of Vishnu-purana. The Vishupurana is content oriented. Descriptions do not cover much of its area. “Puranas have five main features.
They are Sarga Pratisarga Vamsa Manvantaras and Vamsanu Charita. Sarga means creation, Pratisarga means dissolution and secondary creation by Kasyapa prajapati etc.
The dynasties of the rulers and the historical events of the famous persons occupy important portion of the puranas. The narrators of such puranas were known as Sutas.
Chanakya in his Arthasastra mentioned that rulers must listen to the Itihasas and Puranas in the evening time. (5th Adhyaya 13th,14th prose pieces). The wisdom gained by doing so, perhaps helped them in their administration.
Vishnupurana is the most authentic for the Srivaishnavas. Sree Krishna devaraya depicted Stories from Vishnupurana in his Telugu poetic work Amuktamalyada. The purnana is authentic for others as well.