| Cabinda |
| California |
| Cambay |
| Cambodia |
| Cameroon (German) |
| Cameroon |
| Canada |
| Canary Islands |
| Cantabria |
| Cape Colony |
| Cape Verde |
| Carolina, North |
| Carolina, South |
| Cartagena de Indias |
| Catalonia |
| Cayman Islands |
| Ceará |
| Central African Republic |
| Central America |
| Ceylon |
| Chad |
| Chile (1810-1814) |
| Chile (since 1817) |
| China (Empire) |
| China (Republic) |
| China (Soviet Republic) |
| China (Provisional Government) |
| China (Nanjing) |
| China (People's Republic) |
| Cisalpine Republic |
| Ciskei |
| Cispadane Republic |
| Cochin |
| Cocos Islands |
| Colombia |
| Colorado |
| Comoros |
| Committee of Members of the Constituent Assembly |
| Confederate States of America |
| Congo (Brazzaville) |
| Congo (Free State) |
| Congo (Kinshasa) |
| Connecticut |
| Cook Islands |
| Corrientes |
| Corsica |
| Costa Rica |
| Côte d'Ivoire |
| Courland |
| Crete |
| Crimean Khanate |
| Croatia (1941-1945) |
| Croatia (since 1991) |
| Cuba (1868-1878) |
| Cuba |
| Cundinamarca |
| Curaçao |
| Cyprus |
| Cyprus (Northern) |
| Czech Republic |
| Czechoslovakia |