The Dorians: Around 1200 BCE, a new group, the Dorians, came down from the north. The early tribes who lived on the Greek peninsula never really had a chance to beat the Dorians. These early people had stone weapons. The Dorians had iron weapons. 

Historians and archaeologists have found written records left by the early tribes on the Greek peninsula that tell how they tried to save their women and children by moving them from one town to another, and how they stockpiled war material in preparation for the next battle with the Dorians. 

The Mycenaeans were great warriors, but the Dorians had iron weapons. The Mycenaeans really did not have a chance against such superior equipment. Around 1200 BCE, all written records stop because the Dorians had won. All written records stopped for about the next 400 years. For the next 400 years, Greece fell into a dark age.

The Dorians had no written language. They did not paint pictures of their life on vases and pottery. The 400 years that the Dorian people ruled ancient Greece is called the Grecian dark ages. A dark age is time a period of time in history that we usually know very little about because people did not write things down. But the Greek dark age was different. We know quite a lot about this period of time because of the storytellers. 

The Dark Ages ended, around 800 BCE, with the development of the Greek city-states.