The correct answer is: An asteroid impact.
The scientists call it the extraterrestrial impact theory. It states that a giant, six mile wide meteor hit the Earth around 66 million years ago. As a consecuence, clouds of iridium dust and other materials were thrown into the air, blocking the sunlight for years. This lead to the extintion of the dinosaurs who were not able to feed themselves as plants didn't grow. Photosynthesis was not possible and food chains could not be completed. When the dust settled the greenhouse gases were locked in the atmosphere causing a general increase of temperature.
Mostly, people believed that economic stability and the cooperation between the countries, including economic dependency, would be the best promise of peace. Because of this, international organisations, such as European Union and the United Nations were established.
The Aryan Empire lasted 100 years and the Mauryan Empire lasted 300
