Causes of the Thirty Years' War

The Thirty Years’ War devastated Europe in the early part of the 17th century. But what were the causes that led to the momentous event that changed the face of Europe? What were the situations and events that finally sparked the Thirty Years’ War?

Kalmar Union

Queen Margaret

Unions formed by marriage were usual in the past. They were mostly formed by marriage of one ruling royal family to another. With marriage a strong alliance and relation would be formed. It was also another way for a strong kingdom to place a strong influence over another lesser royalty. One of the most well-known union formed by marriage was a Baltic union called the Kalmar Union.