Cards first appeared in Europe around 1375. Before this time there was no mention of cards in any of the records we possess, even those that ought to have mentioned cards, such as proscriptions on gaming. After this time, cards suddenly appear as a curiosity and as a threat to be extinguished, popping up in cities across the continent.
Soon after the mention of cards as foreign curiosities and threats to productivity, we start seeing information about the cardmakers themselves. The biggest centers of card production were located in what is today southern Germany, but most countries also produced at least some of their own cards independently.
The question of who brought cards into Europe is one that has been mostly ignored by the academics researching this subject, who are in general most concerned with proving that their nation had cards first. French academics can prove they were in France first, and Italian and German scholars can do exactly the same. Because of this sense of competition, the records we have right at the cusp of the introduction of cards are all suspect, and it is challenging to glean any reliable information from them.
What we know about how cards got into Europe comes mostly from logic and deduction. They must surely have been traders, for example — cards followed the Silk Road and appeared first in Vienna; who else could this be, right? Most modern scholars are quite cautious, and stick carefully to this story as it makes a very good null hypothesis. Attempting to craft a slightly more interesting history would be academically risky, because of the wide variety of pretty lies that have circulated, mostly about gypsy fortune tellers and long-lost doctrines of imaginary cultures.
Really, though — modern scholars ought to face the possibility that the Romani people may in fact have been the ones to carry both playing cards and xylography into Europe. They came from the same region, they travelled at the same time, they appeared in the same places. They have been traditionally linked in our minds for a very long time, too — and while that doesn’t necessarily mean that gypsies are all fortune tellers or that tarot cards will tell us anything about their past, it is important to remember that stereotypes normally come from somewhere.