Clearly they made an impression, if you search for the countries in a manner we have previously used to probe underlying stereotypes about places, the countries' performance in the tournament ranks highly.
If you search "Why is [placename] so.." or "Why does [placename].." in French Google, unsurprisingly not many locations return autocomplete results:
To be fair, how much do you know about what's going on in Brittany right now?
For the ones that do, most opinions seem to be formed on current news events, like the Scottish Referendum or Euro 2016.
If not, they are mostly dictated by football. The main query about Manchester, for example, is why Manchester City FC has three stars on their (old) badge.
Another query about the North of England raises an eyebrow - we assume it's to do with the War of the Roses.