| Name: | Organization of American States (OAS) |
| Foundation date: | 30 April 1948 |
| Headquarters: | Washington, DC (USA) |
|
OAS flag |
| 30 April 1948 | |
| 28 February 1967 | Barbados, Trinidad and Tobago |
| 25 June 1969 | Jamaica |
| 8 May 1975 | Grenada |
| 8 June 1977 | Suriname |
| 22 May 1979 | Dominica, Saint Lucia |
| 5 December 1981 | Antigua and Barbuda, Saint Vincent and the Grenadines |
| March 1982 | Bahamas |
| 12 March 1984 | Saint Kitts and Nevis |
| 8 January 1990 | Canada |
| 8 January 1991 | Belize, Guyana |
