Controversial Period
We cannot fix a precise date for the beginning of this civilisation, but certain indications synchronize it roughly with the village cultures of Baluchistan. The site of Rana Ghundai produced a stratification which showed, in the third phase of the village's history, a type of pottery with bold designs in black on a red background. From evidence discovered by Sir R.E. Mortimer Wheeler in 1946, it seems that city of Harppa was built on a site occupied by people using similar pottery. There is no evidence of the date of the foundation of the other great city of Mohenjo-daro, for its lowest strata are now below the level of the Indus, whose bed has slowly risen with the centuries; though diggings have reached 30 feet below the surface, flooding has prevented the exacavation of the earliest levels of the city. From the faint indications which are all the evidence we have, it would seem that the Indus cities rose in the first half, perhaps towards the middle, of the third millennium BC.
Difference between Pre Harappan and Proto Harappan Cultures : Cultures that preceded Harappan culture are pre Harappan, while proto Harappan cultures are those pre Harappan cultures which have some close similarities with the Harappan culture or which may be said to have anticipated certain essential elements of Harappan culture. In short, all proto Harappan cultures are necesssarily pre Harappan cultures, but all pre Harappan cultures are not necessarily proto Harappan cultures.
Periodization of Indus Valley Civilization
| Date Range | Phase | Era |
| 5500-3300 |
Mehargarh II-IV |
Regionalization Era |
| 3300-2600 |
Early Harappan (Early Bronze Age) |
|
3300-2800 2800-2600 |
Harppan - I(Ravi Phase) Harappan 2(Kot Diji Phase,Naisharo 1, Mehrgarh VII) |
|
| 2600-1900 |
Mature Harappan (Middle Bronze Age) |
|
| 2600-2450 |
Harappan 3A (Nausharo IIO) |
Integration Era |
| 2450-2200 |
Harappan 3B |
|
| 2200-1900 |
Harappan 3C |
|
| 1900-1300 |
Late Harappan (Late Bronze Age) |
|
1900-1700 1700-1300 |
Harappan 4 Harappan 5 |
Localization Era |
|