Main countries that participated in world war 1
- Countries that participated in world war 1
- All countries that participated in world war 1
- Main countries in world war 1
- Countries that participated in world war 1 and 2
- What main countries fought in world war 1
- List of countries that participated in world war 1
- Main countries involved in world war 1
- Two main countries in world war 1
- World war military
- Countries world war 2
- World war 1st and 2nd
- World war second
- Top 10 countries with the most battles won