Europe was emerging from the Middle Ages, its kingdoms vying for power, trade and influence. With the Ottoman Empire controlling key land routes to Asia, the search for alternative paths to wealth became an obsession.

Ships began to set sail from Spain, Portugal, England, France and the Netherlands, driven by a mix of ambition, necessity and curiosity. These expeditions had one primary goal: access to the riches of the East—spices, silk and gold.

But they also carried the seeds of something far greater: the beginning of a globalized world.

European monarchs backed these voyages with fierce competition, seeking new trade routes, colonies and territorial claims. While many aimed for Asia, one of the most consequential discoveries was the Americas.

The Great Dying In The Americas Wreaked Havoc—In More Ways Than One

Old World diseases like smallpox, measles and influenza traveled in the holds of European ships, spreading rapidly in lands where the immune systems of indigenous populations had never encountered them. What followed was one of the deadliest pandemics in human history—a catastrophe so vast that its effects rippled beyond human civilization and into the environment itself.

The Great Dying began with first contact. For the indigenous peoples of the Americas, these diseases were foreign invaders, spreading faster than European conquest itself. Entire villages were wiped out before their people even saw a single European soldier.

Smallpox, in particular, tore through the continent, leaving a trail of empty settlements, abandoned fields, and societal collapse. Some estimates suggest that 50 to 90% of the indigenous population perished—an event so devastating that historians compare it to the Black Death in Europe, but on an even larger scale.

But the consequences didn’t stop at human loss. The Great Dying had an unexpected, planet-wide impact—one that helped tip the Earth into a colder era.

With tens of millions of people gone, vast stretches of cultivated land were left untended. Croplands, orchards and settlements were overtaken by forests, grasslands and wetlands. This sudden reforestation of the Americas absorbed massive amounts of carbon dioxide (CO₂) from the atmosphere—so much, in fact, that some scientists believe it contributed to the Little Ice Age, a period of global cooling that lasted for centuries.

The Little Ice Age—How A Perfect Storm Of Events Froze The Planet

The Little Ice Age, which lasted from the early 1300s to the mid 1800s wasn’t caused by a single event, but by the compounding effects of a series of environmental shifts, volcanic eruptions and the unintended consequences of human absence.

The 1257 eruption of Samalas, one of the most powerful in recorded history, is believed to have kicked off the cooling trend. Later eruptions—Huaynaputina (1600), Laki (1783) and Tambora (1815)—spewed immense amounts of sulfur dioxide into the atmosphere, blocking sunlight and plunging global temperatures.

Tambora’s 1815 eruption alone triggered the infamous “Year Without a Summer” in 1816, when snow fell in June and July, crops failed and famine spread across continents.

Adding to the cooling, the Sun itself entered an unusually quiet phase. During the Maunder Minimum (1645–1715) and Spörer Minimum (1460–1550), sunspots nearly vanished, weakening the Sun’s energy output. With less solar radiation reaching Earth, winters became even more brutal.

These forces—volcanic winters, a weakened Sun, and the carbon drop from the Great Dying—worked in tandem, keeping the planet locked in a deep freeze for centuries.

What Is The Ultimate Takeaway From The Great Dying?

Some argue that humans are an invasive species, an unnatural force disrupting the balance of nature. And in many ways, we are.

However, we are also deeply intertwined with the planet’s rhythms, capable of influencing its climate on a massive scale—sometimes by accident. The lesson isn’t just that we can cause destruction, but that the Earth self-regulates in ways beyond our control. What happens next depends not on whether we act, but how.

If our absence altered the Earth so dramatically, what does that tell us about our presence? Take a 2-minute test to see where you stand on the Climate Change Worry Scale.