For most of human history, western Europe has contained technologically-backwards and politically-disorganized groups of people. However, during a 400 year period starting around 1500 AD, Europeans conquered much of the World. For thousands of years preceding the European ascendancy, Chinese, Mesoamerican, and African civilizations were both technologically and politically far more complex than the tribes of Western Europe. So, why were a few tribes in western Europe, in a relatively short period of time, able to spread their languages, economic systems, political systems, clothing styles, institutions, religions, people and technology across much of the world? In addressing this question, we’ll build a general theory of societal evolution that accounts for the differences we observe among human groups, and we’ll apply this theory to understanding the European expansion that occurred after 1500 AD. (Undergraduate)