There is a theory that the people of Indus-Saraswati civilization were quite peaceful and this makes them quite different from other Bronze age civilizations like Egypt, Mesopotamia or the Minoan.
But, the Indus cities had fortified walls. Archaeologists have found arrowheads, and spearheads, besides a small number of daggers and axes. Sir Mortimer Wheeler believed that the tools could have been used for hunting and not warfare. The walls, it is believed, were built to protect the city against flood or to impress. There is no evidence of swords or body armor or military equipment like swords or catapults. Even the Indus art does not depict warfare or killing. Probably the residents were concerned with defense and had no experience in warfare. All this caused Mark Kenoyer to say it is possible that the Indus civilization, which evolved over a period of 4000 years from the local cultures of Mehrgarh, managed to resolve conflict without warfare. If so, this would be a unique example of living among the bronze age civilizations – an early example of ahimsa.[The Peaceful Indus People]
Now a new paper suggests that the Indus-Saraswati people were not so peaceful after all.
Well, it turns out that there may have been some amount of brutality in the Indus cities too. Skulls were caved in, noses were broken. One can’t be entirely surprised – a purely non-violent society on such a large scale sounds like a pipe-dream. According to , out of eighteen skulls studied from the later Harappan period (1900-1700 BC), nearly half had suffered heavy trauma. More interestingly, they report that the prevalence and patterning of cranial injuries, combined with striking differences in mortuary treatment and demography among the three burial areas indicate interpersonal violence in Harappan society was structured along lines of gender and community membership. To wit, the farther you lived from the city centre (or, possibly if your remains were found outside the city sewers), the likelier you were to have had a more violent death. Furthermore, the Harappan culture appears to have become more violent over time, with women being more affected in the later periods.[Some Indus Gossip]
Prof. Jim Shaffer asks people to look at the period during which this violence happened
Jim Shaffer, professor at Case Western University, tempers this finding as a characterization for Indus civilization as a whole by pointing out that the sample comes from a late period in the history of Harappa, between 1900 and 1700 BCE, when Indus civilization was in decline.[Indus civilization continues to intrigue]