Portuguese — Why use definite articles in front of possessive nouns? Why the extensive use of proposition contraction?

Question

I can speak Spanish and French, and I am currently learning Portuguese. During my learning, I realized that there are some unique features in Portuguese — I don't speak Italian, so I don't know if those are also present in Italian. In particular, I found the following quite amusing:

1. The fact that you can use definite article in front a person's name or possessive pronoun (this is the opposite of what we have been taught in English, French and Spanish, and I was surprised when I first learnt it): a minha roupa (my clothes), O João ("the" João)

2. Contraction of articles is extensive in Portuguese. Spanish only has a + el ⟶ al and de + el ⟶ del, and French have some, for example, de + le ⟶ du and a + le ⟶ au. But, in my impression, all propositions in Portuguese are contracted with definite pronoun (o, a), demonstrative pronoun (essa, esse,...), indefinite pronouns (um, uma)

Are there specific terminologies for the above-mentioned phenomena in Portuguese? And why has Portuguese absorbed and combined so many features from Spanish and French? As someone who can speak both languages, it did make it easier to understand some grammatical rules in Portuguese.

Answer 1

It is not so uncommon for langueges to put articles in front of personal names, it happens, for instance, in the South Tyrol dialect of German, so it is just a thing that happened and it is one of the features that distinguish portuguese in comparison to many romance languages. If you don't use an article it may sound more arcaic or even formal, although in a specific subdialect of the carioca dialect people don't use the article before names of close friends and family. The same goes for the use of the article before possessive determinants, it has no strong distinctive effect. It also happens in italian.

The contractions are another pretty common phonetic phenomenon and it was quite easy to occur in portugues since the articles lost their initial l-, leaving a hiatus between the preposition and the article (pretty much the same thing happened in Spanish with de + el). This contractions happened really early in the middle ages.

The thing is: Portuguese didn't "absorbed" features from Spanish and French, they were independent phenomena that naturally occurred in Portuguese.