नैमिषारण्ये At Naimiṣa Forest

The opening adhyāya is the threshold: a frame within a frame within a frame. We stand with the rishis at the long sacrifice of Śaunaka in the Naimiṣa forest. A traveller arrives — Ugraśravas, son of Lomaharṣaṇa, of the sūta class whose work is the keeping and recitation of dynastic memory. The rishis greet him with the formality due a learned guest and ask what he has been doing. He tells them: he has been at the snake-sacrifice of king Janamejaya, where he heard the rishi Vaiśampāyana recite the whole of the great itihāsa इतिहास itihāsa iti + ha + āsa — thus, indeed, it was A narrative tradition that asserts itself as having actually happened — "the way it was." Not myth, not chronicle, but a third thing. full entry → composed by Kṛṣṇa Dvaipāyana Vyāsa. Will Sauti recite it for them? He will.

Before the recitation can begin, however, Sauti offers a long synopsis: the text we are about to hear has many openings, and a learned audience must be told which of them he intends. He gives a sketch of the whole — the births of the principal figures, the rivalry of the Kuru cousins, the dice game, the exile, the war, its aftermath — and only then settles into the actual narrative.

What the first adhyāya tells you, structurally, is that the Mahābhārata is self-aware about being told. The frame voices are not pretext; they are part of the architecture. Every event you will read about has already been narrated, by someone, to someone, for a reason.