Indo-Gangetic plains

The Indo-Gangetic Plain, also known as the Indus-Ganga and the North Indian River Plain, is a 255 million hectare (630 million acres) fertile plain encompassing most of northern and eastern India, the eastern parts of Pakistan, and virtually all of Bangladesh. The region is named after the Indus and the Ganges, and encompasses a number of large urban areas. The Indus-Ganga plain is bound on the north by the Himalayas which feed its numerous rivers and are the source of the fertile alluvium deposited across the region by the two river systems. The southern edge of the plain is marked by the Chota Nagpur Plateau. On the west rises the Iranian Plateau.

The region is known for the Indus Valley Civilization, which was responsible for the birth of ancient South Asian culture. The flat and fertile terrain has facilitated the repeated rise and expansion of various empires, including the Gupta empire, Kanauj, Magadha, the Maurya Empire, the Pala Empire, the Mughal Empire and the Sultanate of Delhi – all of which had their demographic and political centers in the Indo-Gangetic plain. During the Vedic and Epic eras of Indian history, this region was referred to as "Aryavarta" (Land of the Aryans). According to Manusmṛti (2.22), 'Aryavarta' is "the tract between the Himalaya and the Vindhya ranges, from the Eastern Sea (Bay of Bengal) to the Western Sea (Arabian Sea)". . During the Islamic period, the Turkish, Afghan and Iranian rulers referred to this region as "Hindustan" (Land of the Hindus), deriving from the Persian term for the Indus River. This term was later used to refer to the whole of India but even into the modern era, the dialect of Hindi-Urdu spoken in this region is called Hindustani, a term which is also used for the local music and culture.

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