Greetings from Croatia!
I'm sure most Croatians would know who Mariah is, and just like in the USA, there cannot be a Christmas season without 'AIWFCIY,' it's just that I don't think I've ever met an actual fellow fan, and she's not that often on TV, for example -- even on talent shows her songs are seldom performed!?
Now granted, I wasn't even born when Mariah was in her prime commercially, but if you'd asked me not more than six short years ago to enumerate as many MC songs as I could, I probably would've only thought of 'Without You,' 'Hero,' 'We Belong Together,' 'AIWFCIY' and 'When You Believe.' I also had a mixtape like 10 years ago which had 'Get Your Number,' but I don't think I knew it was an MC song.
The point is, I assume most people my age (around 20 years old) are like that here - most probably wouldn't know more than 2 or 3 of her songs. I guess she never quite reached that level of fame like Michael Jackson, Madonna, or even P!nk and Bruno Mars (to name a couple of more recent singers), though, once again, things might have been different in the 90s. But at that time, dance/hip hop music, electronica and europop were all the rage here, so IDK. Be as it may, she certainly has influenced some Croatian pop/RnB singers.
Jeez, I've been rambling for so long; I can be so very garrulous!
Now I don't think I have to ask you where you are from, because that is evident from your username I have the impression that she is rather popular in Brazil, given the 10+ weeks at number one that 'I Want To Know What Love Is' achieved there. I hope to one day visit Brazil, since I am a student of Portuguese. What do you think, might I in that case stumble upon some Mariah fans?
I hereby conclude this long-a*s wall of text. Sorry, y'all!