Jain migration route to the West from the East is tied to the famine led by Bhadrabahu.

• The big event: during a severe famine in Magadha (around 300–200 BCE), Acharya Bhadrabahu led a large group of Jain monks and lay followers south to Karnataka to survive. A parallel group stayed in the north. This crisis is the traditional basis for the split into the two main Jain traditions (Digambara and Śvetāmbara) and for the later spread of Jain communities toward the western coast and beyond. ( jainknowledge.com)

• The westernward route (often described as the Uttarapatha or north‑west route): those who went west and north from Magadha traveled along the ancient northern Indian corridor (Uttarapatha), passing through regions such as Pushkalavati (near today’s Peshawar), Kabul, and Bamyan, and then toward Bahlika (the northwest) and eventually reached western ports and regions like Saurashtra and the western coast of India. This movement laid foundations for Jain communities in Gujarat, Maharashtra (west coast), and nearby areas, and contributed to the Śvetāmbara presence in the west. ( en.wikipedia.org)

• The southern route: Bhadrabahu’s group went south to Shravanabelagola (Karnataka), where Chandragupta Maurya is also linked in Digambara tradition. This southern migration is the counterpart to the western/north‑west migration and explains the geographic split between Digambara (often associated with the naked order of monks) and Śvetāmbara (white‑clad) lineages. ( jainknowledge.com)

In short: the westward migration from the east largely followed the northern/Uttarapatha corridor through the northwest (Pushkalavati, Kabul, Bamyan) toward Bahlika and the western coast, while a parallel southern migration went to Karnataka. Both streams originate from the famine era under Bhadrabahu and are central to the Digambara–Śvetāmbara split in Jain history. ( jainknowledge.com)

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