History is littered with stories of fallen empires and civilizations that overstretched themselves, but sometimes there are signs that show an ancient lifestyle that we know little to nothing about why they disappeared or didn't at least last longer into history. Here we take a look at a few of these civilizations that we know existed, but we don't know what happened to bring their power to an end.
1. The Harappan Civilization
Also known as the Indus Valley civilization, this was a bronze age (3300–1300 BCE; mature period 2600–1600 BCE) mainly in the northwestern regions of South Asia, with Harappa being one of its two main cities which was one of the first of the civilization's settlements to be discovered by modern archaeologists. At its peak, it is thought to have had 5 million people as part of its population, but in 1800 BCE it began to decline and eventually it disappeared as a whole.
Speculation as to the fall of the Indus Valley people ranges from environmental changes to invasion of Aryan cultures but there are no firm reasons or evidence to solidly suggest either of these are the case, and they are little more than educated guesses.
2. The Anasazi
Anasazi are also known as the Ancestral Puebloans who were an ancient Native American culture that spanned the present-day Four Corners region of the United States, comprising southeastern Utah, northeastern Arizona, northwestern New Mexico, and southwestern Colorado. They would live in cliffside dwellings as a form of protection and often these would be carved out of the very stone of the cliff itself.
Between the 12th and 13th centuries, the Anasazi disappeared from their ancestral homelands with possible factors for this being global or regional climate change, prolonged periods of drought, cyclical periods of topsoil erosion, environmental degradation, deforestation, hostility from new arrivals, religious or cultural change, and influence from Mesoamerican cultures. Many of these possibilities are supported by archaeological evidence, but the most popular theory remains that they were abducted by or were part of an alien race. So prevalent is this theory that it was even featured in an episode of the X-Files.
3. The Minoans
Considered by most in the scientific community to be the oldest known civilization in Europe, the Minoans lived in what is now known as Crete until; around 1400BC when it is thought that a volcano destroyed the culture but it has been argued that it could not have possibly have destroyed the whole of the civilization.
Significant Minoan remains have been found above the Late Minoan I era Thera ash layer, implying that the Thera eruption did not cause the immediate downfall of the Minoans, and it is most likely this was then seized upon by an invading force that brought about the end of the Minoan civilization, but nothing concrete has been agreed upon.
4. The Clovis
The Clovis culture is a prehistoric Paleo-Indian culture, named for stone tools of the society found near Clovis, New Mexico, that dates back to 10,000 BC, meaning that they are thought to be the first human inhabitants of the New World. Replaced by several more localized regional cultures from the time of the Younger Dryas cold climate period onward, it has been speculated that a sudden cold period killed off the culture.
Others have suggested a possible comet impact for their demise, but most hypotheses have been criticized because of misinterpretation of data and the lack of confirmatory evidence.
5. The Myceneans
Mycenaean Greece (or Mycenaean civilization) was the last phase of the Bronze Age in Ancient Greece (c. 1600–1100 BC) and represents the first advanced civilization in mainland Greece. Showing decline by 1200BC, only a hundred years later they were completely gone, and it is thought that this is either because of invasion or natural disaster, such as earthquakes.
However, evidence of social unrest also appears throughout the civilization's history, and it may well have torn itself apart. No definitive conclusion has been drawn as of yet to the disappearance of this culture.
6. Easter Island
The first settlers on Easter Island would have been Austronesian Polynesians and are likely to have arrived from the Marquesas Islands from the west and are known primarily for erecting enormous stone statues (called Moai) in the shape of human heads (the bodies buried beneath the ground) and lining the island’s coastline with them.
European accounts in 1722 (Dutch) and 1770 (Spanish) reported seeing only standing statues, but by James Cook's visit in 1774 many were reported toppled and it is thought that this was a sign of internal struggles with the civilization and this was a sign of rebellion or overthrown power. However, no completely valid reasons have been found with the nearest idea yet being that the society used up all of its natural resources.
Catalhöyük was a very large Neolithic and Chalcolithic proto-city settlement in southern Anatolia, which existed from approximately 7500 BC to 5700 BC, and flourished around 7000 BC. Considered the oldest city known to man, homes were built in a honeycomb-like structure with inhabitants entering them through holes in the roofs.
Thriving for nearly 2,000 years, there are currently no theories as to why the civilization might have vanished.
A pre-Columbian Native American city dating from 600–1400 CE, it was a collection of man-made mounds and large wooden structures, including one that was designed to track the movement of the stars across the night's sky. Although incredibly advanced in some ways, it is thought that poor sanitation may have led to the spread of disease that eventually destroyed the civilization although this cannot be confirmed.
Famine hunting, deforestation, and flooding are all factors that have also been pointed to as possible reasons why the site was abandoned and never reoccupied by other indigenous cultures.
9. Nabta Playa
Nabta Playa was once a large internally drained basin in the Nubian Desert, located approximately 800 kilometers south of modern-day Cairo or about 100 kilometers west of Abu Simbel in southern Egypt, but now it is filled with various archeological sites that point to a community of farmers, craftsman, and cattle workers in the Egyptian Sahara.
With deep wells and communities built with some planning in mind, it is thought that this society was far more advanced than their contemporaries who lived closer to the Nile Valley with circular configurations of rocks and twigs discovered in their area indicating that they may well have been early astronomers. However, their disappearance remains a greater mystery with shifting monsoon patterns thought to have had a hand in it.
A fictional island mentioned in the work of ancient Greek writer Plato, Atlantis supposedly was an extremely advanced society that attacked ancient Athens, only to be repelled and then fall out of favor of the Gods who then submerged it in the sea. Despite its relatively small mention by Plato, it has had a massive impact on European literature and has been mentioned several times later. This repeated occurrence throughout history with Plato's vagueries of its existence indications of the time of the events—more than 9,000 years before his time—and the alleged location of Atlantis—"beyond the Pillars of Hercules"—has led to much pseudoscientific speculation about it actually being real.
There remains no evidence of this, but some consider this either a possible cover-up or that it has just not been found yet. Investigations into civilizations that may have inspired Atlantis have also yielded few tangible results with most still believing Plato created the story from scratch.