If you didn't already know this, then we will tell you now - originally, all humans had brown eyes. Having blue eyes is actually the result of a mutation that one of our ancestor's would have experienced. A similar mutation exists within people with blonde hair, as we all used to have brown hair.
Ironically enough, blonde eyes are seen as particularly beautiful - perhaps because of the rarity of them in certain regions of the world, but Estonia is definitely not one of those areas. Located in Europe, Estonia has the highest percentage of citizens with blue eyes, 99%, according to Hans Eiberg of the University of Copenhagen.
Close runner ups include Germany, where 75% of citizens have blue eyes, and in Denmark, around 85%-90% of citizens are said to have blue eyes.
Researchers have all come to the conclusion that blue eyes were predominant amongst our ancestors that lived in a few regions of the world. These regions are Ireland, the Baltic Sea, Northern, Southern, and Eastern Europe, as well as certain parts of Western Asia [most notably Afghanistan, India, and Syria]
To learn more about those beautiful blue eyes some of us have, click the source!