“On The Idle Hill Of Summer” examines the state of Europe in the early 20th century, and how growing unrest among the working classes set the stage for tension between European empires. The episode begins with the expansion of the German economy and population that turned the country into the strongest military power in Europe. Then highlights how the fears that followed this explosion in power brought together rivals Britain and France against a common enemy, and with the help of Russia, how an alliance was formed, which encircled German and Austrian powers. The episode ends with the shooting of Archduke Franz Ferdinand and the death of peace across the European groups.