Subject
- Sovereignty7
- River navigation6
- International relations4
- Boundaries3
- Diplomacy3
- Military occupation3
- Boundary disputes2
- Imperialism2
- Railways2
- Slave trade2
- Trade (practice)2
- Treaties2
- Administrative reform1
- Concessions1
- Economic reform1
- First World War (1914-1918)1
- Fortifications1
- Jurisdiction1
- Mail steamers1
- Migrants1