In which John Green teaches you about the Holy Roman Empire by teaching you about Charles V. Charles Hapsburg was the holy Roman Emperor, but he was also the King of Spain. And the King of Germany. And the King of Italy and the Lord of...

In which John Green teaches you about water! So, we talk about resources a lot on Crash Course, and today is no exception. It turns out people can't live without water, which means it's absolutely necessary for civilization. Today John...

In which John Green teaches you about war! Specifically, John talks about whether humanity is naturally warlike, hard-wired to kill, or if perhaps war is a cultural construct. John will talk about the Hobbes versus Rousseau debate, the...

In which John Green teaches you about the Little Ice Age. The Little Ice Age was a period of global cooling that occurred from the 13th to the 19th centuries. This cooling was likely caused by a number of factors, including unusual solar...

In which John Green teaches you about how Islam has interacted with politics during it's history, and how it continues to do so today. Islamist movements are in the news a lot lately, but how did that happen. John will point out that...