There are clues in Mahabharata which tells us about how the itihaas grew to become the longest poem with over a lakh verses. Mahabharata is divided into 18 parvas with Harivamsha as the 19th. The core of it — around 24, 000 — verses are about the war between the Pandavas and Kauravas. Besides this, there are tales of gods, kings, sages, discourses on philosophy, religion, law and various asramas of life. We know that Vyasa was the composer who taught it to Vaisampayana who then narrated it to Janamejaya at his sarpa yagna. Ugrasravas, the suta, then narrated it to others at Namisharanyam. Recently I read a book — A short history of Sanskrit Literature — which elaborates on a theory on how Mahabaharatam came to be.
Here are three verses from Mahabharata which refers to three different lengths
- This verse refers to the first stage that has over 8000 verses
- This is the reference to the 24,000 verses
- This is the reference to the third stage that has over a lakh verses.
It is not just that the number of verses increased; the name of the itihaas changed as well. The very first line in adi parvam refers to it as jayam.
नारायणं नमस्कृत्य नरं चैव नरॊत्तमम
देवीं सरस्वतीं चैव ततॊ जयम उदीरयेत
Then it became bharatam and finally mahabharatam. Was it because it passed through three people — Vyasa, Vaisampayana, and Ugrasravas?
The author of the book, T. K. Ramachandra Aiyar, thinks that the core of Mahabharata is the rivalry of Kurus and Panchalas. Their enemosity is historic. They quaralled for a long time and finally there was a union. The Yajurveda — which was composed in a nearby region — mentions this. The Kathaka Samhita, though speaks of a dispute between Vaka Dalbhya from Panchala and a Dritharashtra who is the son of a Vichitravirya, a Kuru. Over time, the kingdoms split again and engaged in constant rivalry. By the time of Mahabharata, the Kuru and Panchala kingdom were separate.
Prior to the war, there was a turn of events which caused the annexation of Northern Panchala by the Kurus. This is the incident, where Drona defeats Drupada using Arjuna. This event upset the balance of poweer between the two kingdoms. The Kurus were defeated in the war and the Panchalas won along with the Pandavas. (Here is an interesting explanation about the Mahabharata war, not as a rivalry between Kauravas and Pandavas, but as a war between Kurus and Panchalas).
With this background, here is the theory on what might have happened. The defeat of the Kurus would have resulted in various songs glorifying the victory of the Pandavas and their allies. Sutas would have sung this in various assemblies. This would have been Jayam. By the second stage, when it reaches 24,000 verses, the life of Pandavas was elaborated. Krishna was represented as an incarnation of Vishnu and Shiva and Vishnu become more prominent than Brahma. The epic became popular all over bharatavarsha and other additions like the stories of gods and sages were added and it became a treatise on dharmashastra. This was the third stage.
The book became an authority on dharma dealing with religion, law and morality. It was accorded the status of the 5th veda. There are land grants dating between 462 CE and 532 CE, which talks about the one-lakh verse Mahabharatam compiled by Vyasa. There are numerous literary evidence from Sanskrit authors on the stature of Mahabharata. From Ujjayini to Khamboja, the ithihaas was read in temples. It became a national epic.