If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content
The First World War feels almost like a murder mystery, with many suspected causes, and complex motives. Millions of lives were lost in this confusing conflict that gripped the world. Created by World History Project.
Sort by: