Many people think that in the thousands of years following the rise of agriculture, human societies were static. They were not. Empires rose—some flourished, then perished, while others persisted. Most people remained subsistence farmers who kept themselves, or themselves and the ruling elites, alive. Foraging as a way of life was pushed to agriculturally marginal lands. Populations grew rapidly, with estimates ranging from between 1 and 10 million people at the beginning of agriculture to between 425 and 540 million in the year 1500, around 10,000 years later.
In the 16th century, everything began to change, and change with increasing speed. Agricultural development, from simpler farming communities to city-state to empire (and often back again), slowly began to be replaced by a new mode of living. Revolutions in what people ate, how they communicated, what they thought, and their relationship with the land that nourished them emerged. Somehow, those living on the western edge of the continent of Europe changed the trajectory of the development of human society, and changed the trajectory of the development of the Earth system, creating the modern world we live in today. Nothing would be the same again.
A pivotal moment in this shift to the modern world was the arrival of Europeans in what they would name America. The people of the Americas had been isolated from those of Asia and Europe for about 12,000 years, aside from the odd visit from a lost Viking ship to the North American Atlantic shoreline and rare Polynesian forays to the South American Pacific Coast. This separation of humanity occurred because at the end of the last ice age, as the world warmed, there was still enough ice for a few individuals to make it across the Bering Strait from Asia to North America. This window of opportunity to cross did not last long, as most of the sea ice melted, closing the route. The few who made the Bering Strait crossing spread out across the Americas and slowly populated the entire land mass.