5 observances land on 23 September. We have not found a recorded founder for 4 of them.
| Observance | Declared by | First year | Source |
|---|---|---|---|
| International Day of Sign Languages worldwideThe date marks the founding of the World Federation of the Deaf on 23 September 1951 | the United Nations General Assembly | 2018 | Wikipedia |
| Grito de Lares Puerto Rico | no record | — | — |
| Haifa Day Israel | no record | — | — |
| Kyrgyz Language Day Kyrgyzstan | no record | — | — |
| Teachers' Day Brunei | no record | — | — |
"No record" means we could not find one, not that none exists. Where a founder is named, the source is named with it.
Who decides these? Nobody official. A brand, a trade body, a government, or one person with a website. Most are simply asserted and then repeated until they look official. Here, whoever names it first.
Nobody has ever named 23 September here. The next one is Thursday, 23 September 2027.
Thursday, 23 September 2027 has no name yet. It costs $2.