The origins and spread of Proto-Indo-European
This book will argue that the Indo-Europeanizing of Europe—except for its far northeast—began in the seventeenth and sixteenth centuries bc, with military takeovers of lands rich in natural resources. That is a topic quite distinct from questions about the origins and the early spread of Proto-Indo-European. Those questions do have a bearing on the present topic, however, and this chapter will therefore state my understanding of the origins of Proto-Indo-European in the fourth millennium BC and its remarkable spread during the third.
Indo-Europeanists are apparently quite certain that Proto-Indo-European, henceforth PIE, was still being spoken after the invention of the wheeled vehicle, which occurred ca. 3500 bc or perhaps a century or two later. The reason for the linguists’ confidence is that the several branches of Indo-European inherited words for wagon, wheel, yoke, thill and axle.1 Because the various branches also have a word for wool, they must have left the PIE stem at some time after sheep began to be bred for their wool. This too had occurred by the fourth millennium bc (sheep were raised thousands of years before that, but for their meat). After discussing wool, wheels and other items of diagnostic value, Benjamin Fortson dates “a breakup of PIE in the late fourth millennium. Linguists would not be comfortable with a date much later than this.”2
