Research on the Mahābhārata has put an enormous effort into recognizing and dating layers within the text.
Some elements of the present Mahābhārata can be traced back to Vedic times.
The background to the Mahābhārata suggests the origin of the epic occurs "after the very early Vedic period" and before "the first Indian 'empire' was to rise in the third century B.C." That this is "a date not too far removed from the 8th or 9th century B.C." is likely.
Mahābhārata started as an orally-transmitted tale of the charioteer bards.
It is generally agreed that "Unlike the Vedas, which have to be preserved letter-perfect, the epic was a popular work whose reciters would inevitably conform to changes in language and style," so the earliest 'surviving' components of this dynamic text are believed to be no older than the earliest 'external' references we have to the epic, which may include an allusion in Panini's 4th century BCE grammar Aṣṭādhyāyī 4:2:56.
It is estimated that the Sanskrit text probably reached something of a "final form" by the early Gupta period (about the 4th century CE).
Vishnu Sukthankar, editor of the first great critical edition of the Mahābhārata, commented: "It is useless to think of reconstructing a fluid text in a literally original shape, on the basis of an archetype and a stemma codicum.
What then is possible?
Our objective can only be to reconstruct the oldest form of the text which it is possible to reach on the basis of the manuscript material available."
That manuscript evidence is somewhat late, given its material composition and the climate of India, but it is very extensive.

The Mahābhārata itself (1.1.61) distinguishes a core portion of 24,000 verses: the Bhārata proper, as opposed to additional secondary material, while the Aśvalāyana Gṛhyasūtra (3.4.4) makes a similar distinction.
At least three redactions of the text are commonly recognized: Jaya (Victory) with 8,800 verses attributed to Vyāsa, Bhārata with 24,000 verses as recited by Vaiśampāyana, and finally the Mahābhārata as recited by Ugraśrava Sauti with over 100,000 verses.
However, some scholars, such as John Brockington, argue that Jaya and Bharata refer to the same text, and ascribe the theory of Jaya with 8,800 verses to a misreading of a verse in Ādiparvan (1.1.81).

The redaction of this large body of text was carried out after formal principles, emphasizing the numbers 18 and 12.
The addition of the latest parts may be dated by the absence of the Anuśāsana-parva and the Virāta parva from the "Spitzer manuscript".
The oldest surviving Sanskrit text dates to the Kushan Period (200 CE).

According to what one character says at Mbh.
1.1.50, there were three versions of the epic, beginning with Manu (1.1.27), Astika (1.3, sub-parva 5) or Vasu (1.57), respectively.
These versions would correspond to the addition of one and then another 'frame' settings of dialogues.
The Vasu version would omit the frame settings and begin with the account of the birth of Vyasa.
The astika version would add the sarpasattra and aśvamedha material from Brahmanical literature, introduce the name Mahābhārata, and identify Vyāsa as the work's author.
The redactors of these additions were probably Pāñcarātrin scholars who according to Oberlies (1998) likely retained control over the text until its final redaction.
Mention of the Huna in the Bhīṣma-parva however appears to imply that this parva may have been edited around the 4th century.

The Ādi-parva includes the snake sacrifice (sarpasattra) of Janamejaya, explaining its motivation, detailing why all snakes in existence were intended to be destroyed, and why in spite of this, there are still snakes in existence.
This sarpasattra material was often considered an independent tale added to a version of the Mahābhārata by "thematic attraction" (Minkowski 1991), and considered to have a particularly close connection to Vedic (Brahmana) literature.
The Pañcavimśa Brahmana (at 25.15.3) enumerates the officiant priests of a sarpasattra among whom the names Dhṛtarāṣtra and Janamejaya, two main characters of the Mahābhā
Research on the Mahābhārata has put an enormous effort into recognizing and dating layers within the text. Some elements of the present Mahābhārata can be traced back to Vedic times. The background to the Mahābhārata suggests the origin of the epic occurs "after the very early Vedic period" and before "the first Indian 'empire' was to rise in the third century B.C." That this is "a date not too far removed from the 8th or 9th century B.C." is likely. Mahābhārata started as an orally-transmitted tale of the charioteer bards. It is generally agreed that "Unlike the Vedas, which have to be preserved letter-perfect, the epic was a popular work whose reciters would inevitably conform to changes in language and style," so the earliest 'surviving' components of this dynamic text are believed to be no older than the earliest 'external' references we have to the epic, which may include an allusion in Panini's 4th century BCE grammar Aṣṭādhyāyī 4:2:56. It is estimated that the Sanskrit text probably reached something of a "final form" by the early Gupta period (about the 4th century CE). Vishnu Sukthankar, editor of the first great critical edition of the Mahābhārata, commented: "It is useless to think of reconstructing a fluid text in a literally original shape, on the basis of an archetype and a stemma codicum. What then is possible? Our objective can only be to reconstruct the oldest form of the text which it is possible to reach on the basis of the manuscript material available." That manuscript evidence is somewhat late, given its material composition and the climate of India, but it is very extensive.
The Mahābhārata itself (1.1.61) distinguishes a core portion of 24,000 verses: the Bhārata proper, as opposed to additional secondary material, while the Aśvalāyana Gṛhyasūtra (3.4.4) makes a similar distinction. At least three redactions of the text are commonly recognized: Jaya (Victory) with 8,800 verses attributed to Vyāsa, Bhārata with 24,000 verses as recited by Vaiśampāyana, and finally the Mahābhārata as recited by Ugraśrava Sauti with over 100,000 verses. However, some scholars, such as John Brockington, argue that Jaya and Bharata refer to the same text, and ascribe the theory of Jaya with 8,800 verses to a misreading of a verse in Ādiparvan (1.1.81).
The redaction of this large body of text was carried out after formal principles, emphasizing the numbers 18 and 12. The addition of the latest parts may be dated by the absence of the Anuśāsana-parva and the Virāta parva from the "Spitzer manuscript". The oldest surviving Sanskrit text dates to the Kushan Period (200 CE).
According to what one character says at Mbh. 1.1.50, there were three versions of the epic, beginning with Manu (1.1.27), Astika (1.3, sub-parva 5) or Vasu (1.57), respectively. These versions would correspond to the addition of one and then another 'frame' settings of dialogues. The Vasu version would omit the frame settings and begin with the account of the birth of Vyasa. The astika version would add the sarpasattra and aśvamedha material from Brahmanical literature, introduce the name Mahābhārata, and identify Vyāsa as the work's author. The redactors of these additions were probably Pāñcarātrin scholars who according to Oberlies (1998) likely retained control over the text until its final redaction. Mention of the Huna in the Bhīṣma-parva however appears to imply that this parva may have been edited around the 4th century.
The Ādi-parva includes the snake sacrifice (sarpasattra) of Janamejaya, explaining its motivation, detailing why all snakes in existence were intended to be destroyed, and why in spite of this, there are still snakes in existence. This sarpasattra material was often considered an independent tale added to a version of the Mahābhārata by "thematic attraction" (Minkowski 1991), and considered to have a particularly close connection to Vedic (Brahmana) literature. The Pañcavimśa Brahmana (at 25.15.3) enumerates the officiant priests of a sarpasattra among whom the names Dhṛtarāṣtra and Janamejaya, two main characters of the Mahābhā
Mahabharata