Archaeology shows that modern humans have been present
in the
subcontinent for at least thirty thousand years. It does not show by
what route they arrived, but if they came from Africa it stands to
reason that they would have entered from the northwest. Genetic
evidence provides some support for this inference. It points to an
early human expansion from the Horn of Africa along the southern coast
of Eurasia, starting with Arabia and continuing to India and beyond.
There is more direct evidence for the route by which farming first
entered India. Domesticated crops appear by around 6000 B.C. in the
extreme northwest of the subcontinent, and only later are they found in
the rest of India, reaching the south by the third millennium B.C.
Toward the middle of the same millennium the Indus Valley civilization
emerged. It is unlikely to have been an accident that this first Indian
civilization took shape in the part of India that was closest to
Mesopotamia and most similar to it-and never spread to the rest of the
subcontinent.
Far less is known about the Indus Valley civilization
than about that
of Mesopotamia. We have no idea what the people in question called
themselves, or what kind of language they spoke; for convenience we
often refer to them as Harappans, from the name of a major
archaeological site that was once one of their cities. They had
unusually regular town planning but there is no evidence for the
political structures that made this possible. There are two main
reasons why our knowledge is so limited. We have considerable numbers
of inscribed stone seals; but the inscriptions are short, and cannot be
deciphered. In marked contrast to the Near East, this region has left
us no clay tablets or long inscriptions on stone. The obvious
assumption is that the Harappans did most of their writing on
perishable materials; if later Indian practice is anything to go by,
they may have used palm leaves.
The second reason for our ignorance is that their civilization
came to
an end early in the second millennium B.C. The cause could have been
environmental (for one thing, the Indus is a notably unstable river);
or it could have been invasion. Therefore later Indian tradition
retains no memory of the Indus Valley civilization. This does not mean
that the Harappans contributed nothing to the India of later times;
some features of their culture do not go away, including perhaps a
liking for the number sixteen manifested in their system of weights.
But there is no equivalent to the historical information that the
Chinese tradition preserves on the Shang dynasty. The other consequence
of the early end of the civilization is that no outsiders have left us
any account of it.