The Indus Valley, a region of great fertility, defines the eastern edge of the zone in which Near Eastern agriculture developed, based on wheat, barley, sheep, goats, and cattle. To its west lies Baluchistan, the mountainous eastern edge of the Iranian plateau, an area with which it has always been closely linked. Networks of trade routes across the Iranian plateau have often provided distant communications with the civilizations of the Near East, while the Arabian Sea, into which the Indus flows, has allowed seaborne connections with the Gulf and the Near East, with Arabia and East Africa, and with south India, eastern India, and Southeast Asia. The Indus is fed by the five rivers from which the Punjab takes its name, powerful tributaries that water a region of forests and grassland, supporting agriculture along their banks and sustaining pastoral communities elsewhere. These rivers rise in the Himalayas, which form a formidable but not impenetrable barrier between the Indian subcontinent and the lands to its east: the deserts and steppe of Central Asia, as well as China and Southeast Asia beyond. Southeast of the Punjab lay the valleys of the Ganges and Yamuna, which have constituted the center of Indian civilization since the first millennium BCE. This, however, is only a recent configuration, since in the third millennium the ancestor of the Yamuna River may have been a tributary of a major river, the Saraswati, that flowed parallel to the Indus across what is now the Great Indian (Thar) Desert. The desert region and the Aravalli Hills to its south separated the Indus-Saraswati Valley from the central part of peninsular India: They were home, then as now, to hunter-gatherer and pastoral communities. In the west, the Indus entered the Arabian Sea south of its present delta; where today there are the marshy Ranns and the Kutch and Saurashtra peninsulas, in the third millennium there were sea and islands. Agriculture, pastoralism, and fishing have supported the inhabitants of this region for millennia.
Also in the third millennium the Indus Basin was the focus of settlement in the subcontinent, other areas being home to small farming communities, pastoral tribes, and hunter-gatherers. While the rewards of farming in the region were immense, it was and still is tectonically active as the Himalayas inexorably push upward: Earthquakes and major changes in the course of the rivers are therefore an ever present threat, as are devastating floods. The loss of the Saraswati in the second millennium played a major part in the decline of the Indus civilization (also known as the Harappan civilization after one of its
Principal cities, Harappa). In the third millennium this civilization flourished over an area far larger than those of its contemporaries in Mesopotamia and Egypt. But while both of the latter continued to evolve in the second millennium, the Indus civilization disintegrated, and the focus in later times shifted to the Ganges Valley. Nevertheless the Indus civilization left a lasting legacy, setting the pattern for many later aspects of life in the subcontinent, many of which have endured to the present day.
World History
