Why the Seven Years' War qualifies as a world war

The Seven Years' War was understood by contemporaries as a world war on the scale available to them. Geographic reach is separated from the later idea of total war, when industrial capacity allowed far larger shares of people and production to support fighting. Fleets and armies operated across Southeast Asia, India, Africa, the Mediterranean, the Atlantic, the Pacific, the Caribbean, the Americas, and Europe. Modern industrial scale should not erase earlier conflicts that were multinational and fought across many theatres. Familiar war names are retrospective conventions, and the conflict commonly called the Seven Years' War could be counted as closer to nine years.