Ain't AI. Just good ol' bad human design.

Lithuania is in June, but doesn't have the correct colour

Feel free to provide a better map if you have one, I'll update the link

Last I checked Australia wasn't in Europe.

And mothers get the month of May, I presume:)

Symbolic and actually very cool.

Wikipedia explains some history of dates that are not on Saint Joseph's day, but couldn't find a detailed explanation for every country.

Also found out some wild stuff like:

In France lighter manufacturer Flaminaire introduced the idea of Father's Day first in 1949 for commercial reasons. Director Marcel Quercia wanted to sell their lighter in France. In 1950, they introduced "la Fête des Pères", which would take place every third Sunday of June (following the American example). Their slogan is "Nos papas nous l'ont dit, pour la fête des pères, ils désirent tous un Flaminaire" (Our dads told us, for Father's Day, they all want a Flaminaire). In 1952, the holiday was officially decreed.

In Germany it's Jesus-Did-Something-Again-Day (at least here in the South. The North has significantly fewer public holidays because they aren't aware of all those amazing, holiday-worthy things Jesus did around the year).

To be more precise, it's Feast of the Ascension of Jesus Christ - or in German, Christ's Heaven Trip (Christi Himmelfahrt).

same. Thankfully it wasn't fathers day in my home country yet!