What was the Thirty Years War a conflict over?

d.) It was both a religious war and a secular one. The Holy Roman Emperor who was Catholic,. wanted to hold onto his territory, the Protestant German Princes wanted to keep him out. The Danes and the Swedes wanted control of the Hanseatic ports. France wanted to knock the Holy Roman Emperor down a couple of notches. Over the thirty years all these agendas played into the war. In the process Germany was devastated, over 8 million people were killed.