English. French. Italian. Hindi. Greek. Russian. All these different languages can trace their roots to the same origin: Proto-Indo-European, spoken in 4000 BC in the steppe that crosses from Eastern Europe to Central Asia. Whether by migration, diffusion or conquest, the Indo-European languages spread west across Europe, east across Central Asia, and southeast towards India.

Laura Spinney writes about Proto-Indo-European—which never existed in a written form—and its many descendants in her latest book Proto: How One Ancient Language Went Global (William Collins / Bloomsbury: 2025).

Laura Spinney is the author of Pale Rider: The Spanish Flu of 1918 and How It Changed the World (PublicAffairs: 2017), which has been translated into more than a dozen languages, and two novels. Her science writing has appeared in The Atlantic, National Geographic, Nature, The Economist, The Guardian, and elsewhere.

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