Schism: Buddhism

Within India, Theraveda Buddhism grew up in the Dravidian areas, while Mahayana spread from the Indo-European north.

Modern Buddhism is divided into Mahayana and Theraveda (>90%) and the smaller Tibetan Vajrayana, which dominates in a Sino-Tibetan area.

As with the divisions in Islam, and other non-European religions, I can only imagine that the very best scholarship, and certainly the lion's share of the archives, of the histories of Buddhism are in Prakrit languages like Pali (aka Magadhi) and other Indic, Sino-Tibetan, and east Asian languages.

With two exceptions, all Indic, Sinic and Altaic countries are Hinayana, and all Dravidian, Daic and Austro-Asiatic speaking people are Mahayana. Viet Nam and Burma are the exceptions, and I grant that this division, over the ranges of six major language families, has many more influences than I have begun to research.