With convergent growth and falling poverty, the world economy might seem to be out of the woods. Technological advances have put the end of poverty within reach, along with a rebalancing of the international order that is much fairer to the countries outside of the North Atlantic region. Yet complacency would be misplaced, and the rising anxiety le

Ultimately, the larger populations and higher population densities of the Roman and Han empires gave them enormous advantages in scale and technological achievements but did not protect them from conquest by more sparsely settled neighbors—the Germanic tribes of northern Europe, the Turkish conquerors of the eastern Mediterranean, and the nomadic t

For more than three thousand years, semi-nomadic horsemen from the steppes settled, invaded, battled, dominated, and retreated from the temperate lands to the south. Regularly outnumbered, they won their victories through superior horsemanship, cavalry charges, careful planning, and valor. Their names—Huns, Alans, Goths, Turks, and Mongols—still in

Whatever the causes, humanity achieved a measure of “modernity” in the Upper Paleolithic, in terms of language, arts, religion, and other aspects of culture. Human cultures began to flourish. Populations increased, which may have been both a cause and an effect of the cultural changes. Higher population densities may have increased the competitive

during a span of roughly five hundred years, between 800 and 300 BCE, there was a simultaneous emergence of profound philosophical and religious insights in four major civilizations of Eurasia: the Greco-Roman world of the Mediterranean Sea, the Persian world of western Asia, the Aryan world of northern India, and the Han Chinese world of East Asia

The world’s newly discovered lands were thus to be divided between two Catholic nations, Portugal and Spain. Yet other newcomers had quite different ideas. From the early sixteenth century onward, two other rising Atlantic powers, Britain and Holland, both part of the Reformation that rejected papal authority, aggressively contested the papal treat

Paleo-geneticists suggest that much of Europe’s population in fact reflects the admixture of two populations: the first originating with early farmers from Anatolia and the second with the Yamnaya people, itself an admixture of hunter-gatherer populations.

The good news is that there are plenty of opportunities today for major technological shifts to lower T, the human impact per unit of GDP. These include the shift from fossil fuels to renewable energy (wind, solar, hydro, geothermal, and others), which would provide more energy with lower greenhouse-gas emissions. Another opportunity is the shift i

Two voyages of the 1490s—those of Christopher Columbus from the Atlantic coast of Spain to the Caribbean in 1492 and of Vasco de Gama from Lisbon to Calicut, India, in 1498 and back in 1499—decisively changed the direction of world history. Humanity’s understanding of the world and our place in it, the organization of the global economy, the center