Subject
- International relations50
- Colonial administration32
- First World War (1914-1918)29
- Treaties26
- Boundary disputes23
- Foreign policy17
- Armed forces16
- Diplomacy16
- Loans14
- Railways14
- Sovereignty14
- Mesopotamian Campaign (1914-1918)13
- River navigation13
- Slave trade13
- Administration12
- Cars12
- Civil aviation11
- Foreign relations11
- Imperialism11
- Military occupation11