I don’t know what story the poster was referring to, but the use of Roman numerals for centuries is the standard in Spanish and I assume in Portuguese too. If the poster is Brazilian, then his use of Roman numerals is of no surprise.

Exactly, in Brazil is the norm. I didn't think it could not be in english. My only while writing was if it should be "XIX century" or "century XIX". Apparently, neither :)

It was typical for novels I'm the 19th century to be published first in papers, serialized into many installments over a period of time, giving readers an opportunity to talk about it, like episodes of a TV show, and perhaps steer the direction of the story.

Yes. As everything big in culture at the time, it started in France: http://www.gutenberg.us/articles/roman-feuilleton

But it happened in the USA also, as serial novels: http://www.gutenberg.us/articles/Serial_novel

20th century too. The Foundation series was originally a serial.