On the Proto-Indo-European Language of the Indus Valley Civilization (and Its Implications for Western Prehistory)

Many of our attempts to understand the basic causes and conditions of legal, social, political and economic development in the West have been shaped by a particular view of human prehistory, which places the origins of certain key traditions in ancient Greece, Rome and Israel. The developments in ancient Greece and Rome are, moreover, typically pictured as phylogenetically distinct from some of the very first human transitions from hunter-gatherer forms of life into larger-scale urban civilizations that have been found in the archaeological record. Although the so-called "Indus Valley" Civilization (a.k.a. the "Harappan" or "Sindhu-Sarasvati" Civilization) represents one of the very first such successful transformations in our natural history as a species, and although the Indus Valley Civilization long predates similar developments in ancient Greece, Rome or Israel, most scholars deem these early developments irrelevant to Western prehistory because of a specific linguistic proposition: they believe that the Indus Valley Civilization spoke a non-Indo-European language and that its traditions are therefore phylogenetically unrelated to the larger family of Indo-European civilizations that show up in the subsequent historical record (first in ancient Persia, Greece, Rome and India - and then much later in Western Europe and Russia). If this traditional linguistic assumption is wrong, however, then many of our modern attempts to understand the basic causes and conditions of Western development are being shaped by a fundamental misunderstanding - and often to their detriment.

This article argues that, despite certain well-known and long-standing controversies over the issue, we are already in a good enough position to conclude - and with a very high degree of confidence - that the Indus Valley Civilization spoke dialects of Proto-Indo-European. My arguments for this conclusion will be new, and will draw upon a body of evidence that has so far been overlooked in these discussions. A growing number of people have, however, begun to acknowledge this possibility, and I will be suggesting that there are sufficient signs now of a coming paradigm shift with regard to our understanding of early human prehistory to warrant serious attention. If - as I believe - we are in the midst of such a paradigm shift, and if this paradigm shift is like any other, then we should also expect many fruitful discoveries to be emerging from this new perspective.

The arguments in this article have been split into five sections. Section 1 develops a contemporary model of prehistoric linguistic expansion (the "riverine-agricultural model of linguistic expansion"), which suggests that certain major riverine topographies have played a critical role in producing all of the world's major language families - including the Indo-European language family. This model suggests that, during the height of the Indus Valley Civilization, the languages spoken in this region would have almost certainly represented one of the most important and monumental linguistic phenomena ever to have arisen within our natural history as a species. Section 2 then argues that if we assume (plausibly) that significant pockets of this language family should therefore remain in the northwestern portions of the Indian subcontinent, then the Indus Valley Civilization must have spoken dialects of Proto-Indo-European.

Section 3 then considers the objection that tries to reject this last conclusion by rejecting its guiding assumption (i.e., that significant pockets of the Indus Valley Civilization’s language family should still remain in the northwestern parts of the Indian subcontinent). According to this objection, small groups of Indo-Aryan invaders or migrants from the steppes could have simply eradicated the pre-existing language (or languages) of the Indus Valley Civilization by converting the prior populations to Indo-Aryan languages beginning in about 1500 BC. In order to assess this possibility, Section 3 engages in a comprehensive examination of patterns of linguistic replacement from around the world and over the course of world history. This examination reveals an important fact: once a major linguistic phenomenon has reached equilibrium around a major riverine topography in accordance with the riverine-agricultural model of linguistic expansion, there is not one recorded case anywhere in this extensive world historical record where the language family in question has been completely replaced in one of these riverine regions by a different language family through a process of linguistic conversion. We therefore have strong empirical reasons to reject this objection.

Section 4 discusses another common source of resistance to the claim that the Indus Valley Civilization might have spoken dialects of Proto-Indo-European. This objection is based on the perception that this linguistic claim carries with it certain necessary implications about Indo-European prehistory that can be hard to square with the broader body of evidence relevant to this larger topic. In order to address this concern, Section 4 embeds the linguistic claim within a broader narrative concerning Indo-European prehistory that is - I argue - actually better able to explain (or at least render coherent) this broader body of evidence than its main competitors. Hence, the current linguistic proposal - once properly construed - can be understood as the beneficiary of a much broader and more extensive form of evidentiary support.

Section 5 ends, finally, with a direct response to some of Michael Witzel’s important and influential work, which purports not only to establish that Indo-European languages and cultures were first brought to the Indian subcontinent from the Eurasian Steppes sometime between 1500 to 1200 BC but also to trace with some precision the exact timing and path of the Indo-Iranian groups who (in his view) carried these languages and cultures with them. Witzel is one of the most pre-eminent Indologists alive today, and he has collected an important body of evidence relevant to these topics. I will nevertheless argue that Witzel's evidence ultimately underdetermines the choice between his traditional theory and the newer one developed here. In construing his evidence to support his theory uniquely, Witzel has therefore, in effect, mistaken a failure of theoretical imagination for a set of inferences that are required by his evidence. Once our full theoretical options have been made explicit, Witzel's evidence can, moreover, be seen to slightly favor the current theory. The choice between these two theories will, however, become even clearer once Witzel's evidence is harmonized with all of the other evidence relevant to these topics (including all of the new considerations discussed in this article). Based on this entire combined body of evidence, we now have compelling reasons to think that the Indus Valley Civilization spoke dialects of Proto-Indo-European.