Where did Wizard robes come from?

From the artwork Merlin by Earl Norem, to countless random beastiary entries in adventure books, wizards tend to have a few forms.

While they may have a mild style like so, they are often depicted in a sort of whimsical little robe, with a single bright colour, often blue, and adourned with little white stars, or in more conservative robes a singular crescent moon on their pointy hat. So, today I asked myself, what's up with that? Where did it come from? What does it symbolize?

Who even is a Wizard?

The wiktionary entry on wizards leads to a few fascinating discoveries, which I think I definitely heard before. Wizard itself is quite closely tied to all the equivalent forms of wiedźma, ве́дьма, and druid.

I do very much enjoy that nowadays all of those have very specific quite well-defined meanings, however as we see history is sometimes very muddled.

Most of this ties back to some chain from "wise" through "knowledge" to "sight", generally meaning "sage" or "wise-one". This aligns with a statement in there that the actual meaning of "magic user" is a late addition.

In any case back to the original thought:

The hat itself

Sadly it seems this won't have a definitive answer, however some reddit post as if answers were ever found elsewhere does make a few interesting claims. Mostly mentioning many different possible sources for conical hats. I guess this'll have to suffice since the ends are not quite dead but rather there doesn't seem to be any way to determine which answer is correct and does have mentions of anti-semitism so, ... let's get out of here and fast.

Btw, this is quite a fascinating little list.

But what about the moon?

Celestial Bodies

Finally found an answer here.

It mentions certain "French astrological almanacs", which apparently published predictions and methods of divination, might be an interesting read for later.