About Germany's Public Holiday Calendar
The only holiday binding nationwide across all 16 German states is German Unity Day on October 3; the other eight federal holidays share the same date everywhere, but individual states add further regional holidays on top (Catholic-majority southern states typically recognize more religious ones).
Four of Germany's holidays are Easter-linked (Good Friday, Easter Monday, Ascension Day, Whit Monday) and shift every year because Easter Sunday is calculated as the first Sunday after the first full moon following the spring equinox.