The linguistic and cultural diversity is partially due to the differences in climate—for example, the freezing north of the Himalayas in contrast to the jungles of the south—but it is also because of the subcontinent’s rivers and religions. Various civilizations have grown up along these rivers, such as the Ganges, the Brahmaputra, and the Indus. To this day the population centers are dotted along their banks, and the regions, so different from one another—for example the Punjab, with its Sikh majority, and the Tamil speakers of Tamil Nadu—are based on these geographical divides.
