I cannot speak for Portugal, but in Germany, "American" (that is, US American) movies, music and books are considered to be great by default. In media, "American" is a label that signals great entertainment to German consumers, and the most popular films, tv series, books and musical recordings are "Made in America". On top of that, English is considered a "cool" language, everyone learns it in school, it is the language of the music we listen to as teens, and it is the lingua franca of the internet. In Germany, many advertisings for "cool" products feature English slogans, and many products have English or English sounding names.
As for media, while movies are generally dubbed and books translated, American movies usually retain their original titles, even if those titles invovle puns or other features that are difficult for the average German to understand. Books, on the other hand, often receive a new German title, which may or may not be a translation of the English title. But recently many books from the Young Adult category have been published in a German translations with the original (Americal) English title. An example is James Dashner's Maze Runner trilogy:
This may be a phase only, but it stands in the context of the general appreciation of American media and the English language that I tried to briefly describe above, and in fact there are books outside of YA that are published with their original English title, like Oliver Sacks Awakenings:
So, in Germany, a book with an English title would certainly work, especially if it was aimed at a younger audience, no matter if it was originally written in German or any other language.
On the other hand, "the awakening" can be easily translated into German as "das Erwachen", which has a nice sound and feel to it, and I don't think that any publisher would decide on the English title in that case. They would only use the English title, if it sounded better than the German translation.
Maybe this will give you some ideas about your own language and country, which I am not familiar with.