What happened to flags on 17 August
3 flags in the atlas carry this date. The sentence under each one is where that is written down, in its own article.
- Guatemala 1871
The original colors were restored on 17 August 1871, but as vertical (rather than horizontal) stripes in order to distinguish it from other flags and with a new coat of arms.
From Flag of Guatemala on Wikipedia, as it read on 2026-08-26
- Indonesia 1945
Upon Indonesia's declaration of independence on 17 August 1945, it was adopted as the national flag, and has been in use ever since.
From Flag of Indonesia on Wikipedia, as it read on 2026-08-29
- Vietnam 1945
The Viet Minh proclaimed it a "national flag" on 17 August 1945, at a meeting held in the village of Tân Trào in the North.
From Flag of Vietnam on Wikipedia, as it read on 2026-08-29
How a day gets onto this site
A flag is here because a sentence in its own English Wikipedia article puts it on this date, and that sentence is printed above. Nothing was worked out from a year, and nothing was written for the occasion. Every sentence names the article it came from and the version of that article it was read in, so you can go and check it.
The calendar is still short rather than full. A third of the year has no page here, because a flag only gets a day when a sentence in its article puts something on one, and plenty of articles never do. Nothing is invented to fill the gap.