Thank you! I discovered that I don't know the meaning of "riches" in this expression. What does it mean? As for the general meaning of "rise to riches" as far as I understand it is the same as "rise to fame". I mean "rise to fame" means become famous and "rise to riches" means become rich, right?

It's more comon as "rose to riches" as it's usually something used about the past. Common nowadays? Good writing with elegant expressions seem a thing of the past. NOt seen a lot of TV shows that use any form of colourful language apart from the profain. So common? In which circles? Common language seems to be heading towards a lowest common subset. I would have said that virtaully every native English speaker would know this expression, but then I'm old and maybe out of date. Maybe any native speaker of English would understand its meaning.

The expression goes "from rags to riches" implying the person was poor to begin and became rich through hard work and perseverance. You could say "He is a true success story; from rags to riches he worked his way to the top."