The first expansion of civilisation beyond the Middle East was to the Indian Subcontinent. From about 2500 BC to 2000BC there flourished in the Indus Valley an interesting and unique civilisation with strong ties to Mesopotamia. Its cities have been uncovered mainly in present day Pakistan. The two main centres uncovered so far were Mohenjo-daro in the south and Harappa in the north.
The big cities were well planned, with a citadel to the west and residential quarries to the east. Mohenj0-daro covered an area of 60 hectares and possessed an impressive bathing installation most likely for ritual use. In Harappa, large granaries have been found north of the citadel, with adjoining workers' quarters which indicate a relatively high standard of living. Wheat and barley were grown, also peas, sesame and cotton and perhaps also rice. Buffaloes and fowl were the usual domestic animals. Tools were made of bronze.
Thousands of seals have been found, many with an inscription but no writing on sherds uncovered. The pictures on the seals show some gods and various animals, such as tigers, elephants, rhinoceroses and buffaloes. Maritime trade with Mesopotamia seems to have been lively. Archaeologists have assumed that the Sumerians influenced the early Indus valley civilisations. overland trade was plied with Persia and Afghanistan. No signs of writing have been uncovered in the upper (later) layers of these sites and the local civilisations seem to have declined and disintegrated around 2000BC.
India was invaded from the Northwest after 1500BC. The newcomers formed the eastern branch of the great Indo-European movement, which left a common cultural heritage from Greece, through Asia Minor and Iran to India. They called themselves "Aryans". They arrived via Central Asia and entered India from the northwest. They moved only slowly down the Indus valley and eastwards along the Ganges. They were cattle-owning half nomads.
For a long time, agriculture, and not urban life, was typical of the Vedic culture (as their civilisation was called). Its language was Sanskrit, used by the educated upper classes, in which the Vedic literature is composed. Initially, this was an oral tradition - like the Iliad in Greece; its creations were written down only much later. Most of what we know of Aryan culture derives from the Rig-Veda, a collection of hymns transmitted orally by the Brahmans - the priestly caste. Other collections of hymns also survived. The great epic poems of Sanskrit, the Ramayana and Mahabharata, came much later, around the late first millennium BC.
The Aryan settlers tried not to mix with the dark-skinned older inhabitants of India. Although they did not succeed, they thereby initiated the caste system, which strikingly, for three millennia has survived all the changes in Indian society.
The roots of present-day Hinduism too, go back to Vedic culture. Some of the original deities mentioned in the Rig-Veda were Indra, Mitra and Varuna. Their names had also been mentioned in the inscriptions of the Middle Eastern Mitani Empire, showing the common roots of the early Indo-European cultures. In the Mahabharata such later deities as Krishna and Vishnu are already mentioned. The Aryan settlers made another important contribution by clearing land in the Ganges valley, for large scale agriculture.
The fully historical period in India begins around 600BC with the reintroduction of writing. Northern India was divided at that time into several separate states, none of which was of great size of importance. Thus Alexander the Great, on reaching India in 327 BC, did not have to face any unified resistance. But after his death there arose a strong state: the Maurya Empire (321-185BC), which subjected to its rule a greater part of India than any other state, prior to the arrival of Islam and the British.