On the French Caribbean island of Guadeloupe and by the way in all overseas territories we usually have two or three even four our five sometimes Christian names. the minimum is two. You have the given name, the name your parents chose to give you and use it on a day to day basis. Mine is Jean-Marie. Then you have a hidden name connected to the name of the saint celebrated by the Catholic church on the day you were born. For example today in the French calendar (almanach) is March 13. SO the saint is Mathilde; It means that anybody born on this March 13 is using this name, boy or girl, even though it's a girl name; SO you can have men having the name Elisabeth or Catherine. it's very usual and even Marie, Jean and Joseph are a normal part of many names. My second name is Arsène, which was the saint honored in 1952 on October 30.. It was also very practical because they could honor this way an uncle of mine whose first name was Arsène. But if I were to be born on October 30 2016 they would have called me Bienvenue since this is the name of the saint in 2016 registered on October 30 and the saint on that day is Bienvenue which mean welcome. I have two sisters born on May 12th in different years and their second "prénom" (given name) is Achille, from the saint of that day. It's not systematic though. My father was born May 1st. And was'nt called Fête du Travail (Labor Day). He was called after the saints of May 3rd, Philippe Jacques as second and third first names. But I've heard of somebody born July 14 Fête Nationale who was called Fête Nat. lol. It's pretty interesting because when you have such strange names from a girl as Barnabé you can assume she was born around June 11. I had a friend of my family an old man who was blind who had Solange a girl name as his name. He probably was born on May 10. Also saints change dates. You should check the calendar of that given year to be sure... But the strangest thing of all is the extensive use on our west indian islands of nick names. I recently went to a great uncle funeral and I've always known him as Julot. I discovered when he die that his real name was Ferdinand and Ferdinand wasn't even his hidden name. A brother of him died 2 years ago; I'd always known him as Marceau but his real name was Bernard. My paternal grand father's first name was Aquilin Claironisse, which is a very unusual first name but he was usually called Maurice. it is so important that in some marriage records or birth records they sometimes give the information saying the real name plus the nickname using the formula "surnommé X en famille" i.e. "called X within the family circle". One my earliest ancestors from 1813 is called Monrose Baltimore dit Petit Frère. Where you can see that "dit" or "surnommé" means called, said, aka, you name it. I have even discovered recently in my research somebody in Martinique who's nickname around 1848 was Blanchette and the family name Rufen. With the passing of time the name has transformed itself to Rufen-Blanchette and I heard that with the passing of more time they have now descendants in the US with the only Blanchette surname.
As for the maiden surname, as it has been previously mentioned, it's a "nom d'usage". You have the nom de jeune fille, the maiden name. And the nom d'usage is the name you decide to use, it's up to the maid to decide whether she wants to be called x, y ou x-y. there's also a tendency with the younger folks to use both names for their offsprings. In the past around the 1850's, right after slavery was abolished in 1948 this was very much used by some families in Guadeloupe and Martinique. But rapidly they have gone to follow the main stream which is normally, one name, the husband's name. I myself have kids with two names because their mothers are Brazilian and in Brazil they usually have the father's name following the mother's name or vice versa depending of the length of the name, or for harmonious reasons, or whatever reason they have. On their Brazilian passports they have two last names, on the French one only one. Mine.