The French Canadians also have a system of "alias' " called "dit" names. Some families used these alternative names instead of the main surname, some flipped back and forth from one to the other. My Raymond line originally was Bertrand - the first immigrant from Toulouse France - a Jean Baptiste Bertrand dit Raymond dit Toulouse was the son of Raymond Bertrand. For some reason Jean's son Francois took Raymond as his last name and added the dit name Toulouse to it. Although my Raymond's usually used that surname they appear in the 1840 US census as Toulouse in the only instance of that use in my line I have found. Of course the name is often spelled as it is said - Raymo, Ramo, Reymo, Rameau. Although my Chicoine surname usually doesn't use the dit name of Dozois attached to it spelling gets creative. The first immigrant that I have found (1822) learned to write his name in the US and signs it on his daughter's wedding record as "John Chequin" and on others as Chequine. (One branch of the family just gave up and used Shequine which made spelling for people less of a chore!) The Desmarais dit Beaulac line become Demara, Demaray and Bolac with one line using only the dit name. The same occured with my Desrosier surname which turned out to be a dit name for Moreau. Without that realization I could never have traced the line back since they used only Moreau. I could never figure why they didn't stick with Moreau which although creatively spelled Moro or Morrow, is a lot easier than Desmarais! In doing research the dit name is important to know and the proper one for your line is essential. There are more than one unrelated lines of some surnames i.e. Raymond dit Toulouse is different than Raymond dit LaFreniere.
Naming patterns exist in different cultures - on my Irish side there are two - and helpful if you can get all the names of children in correct age order. The eldest son is named for his paternal grandfather, the eldest daughter for the maternal grandmother, second son for maternal grandfather and second daughter for paternal grandmother, next son and daughter are named for parents and in large families siblings of parents names start to appear. (An alternative pattern has first son and first daughter named for father's parents and second for his wife's.) However, this doesn't work if there is another person living in the family with same first name - James Leary and Julia Bresnahan did not name their second oldest son Corneilius for her father since her nephew Cornelius was living with them. Also check out Irish families children's middle names - I discovered that many times a maiden name of a grandmother would appear.
The French Canadians seemed to follow a different pattern with the eldest son named for the father. If that son died a younger brother or brothers would often receive the same name. I would suspect the use of "dit names" was helpful in villages where inhabitants had the same first and surnames. Multiple baptism names occur in this culture with "Marie" and "Joseph" appearing for every child in the family (even boys sometimes got "Marie") for religious reasons. My father disliked his name "Elphege Bernard" and did not know he was baptized "Joseph Elphege Bernard" - if he did he would have used it. Persons dropped or picked up their first names for different reasons - in one case a women dropped her first name and used one of her other baptismal names when she married a man whose sister in law had the same first name. Guess it got confusing.
Nick names were popular especially with the Irish - Mamie, Kitty, Bridie, Maggy, Peggy and Bridie. Some people adopted variations on their name: Cleophas became Charles, Michael Joseph decided he was Joseph Michael. Ellen Helen, Nellie, all were the same woman. Joanna, Hannah, Annie too. The genealogist looking for someone has to try all of the possible variations. Anastasia became Anty and later generations called her Anna. So beware - names can be deceiving and do not get stuck on exact first and last names for the person you are researching.