History from the side of those it happened to
Mathematics
| Date | Country | Category | Title |
|---|---|---|---|
| 24 February 1582 | Vatican City | Mathematics | Gregorian calendar reform is proclaimed |
| 24 February 1582 | Vatican City | Mathematics | Calendar mathematics reshapes civil time |
| 24 February 1582 | Vatican City | Mathematics | A papal decree standardizes a mathematical system |
| 24 February 1582 | Vatican City | Mathematics | Calendar reform spreads unevenly across the world |