For outsiders visiting or learning about Spain, the system of surname inheritance in Spain may seem very strange and foreign. Not surprisingly, all non-Spanish systems seem pretty weird to Spaniards. Humans have a tendency to think "We know what we know and we assume that our way of doing things is the best!" That's one of the most eye-opening things about traveling and learning about other cultures; you learn that the way you and your country have always done things is not the only way. To be a contented expatriate, you have to become very accustomed to saying, "Huh! That's different! It's not necessarily better or worse, but different from what I'm used to." Everything has pros and cons. In this post, I will attempt to explain the Spanish system of last names to non-Spaniards. There are four basic rules to surname inheritance in Spain:
That's it. That's the whole system. To Spaniards, the fact that women in some countries change their last names when they marry seems like a loss of identity. "How can you just give up who you are like that?", they say. Occasionally, they will play the feminist card and claim that giving children only their father's surname is chauvinistic and that the Spanish system isn't because it values the surname of the mother, but if you look closely, the Spanish system is only valuing the mother's father's surname. The truth is that women's surnames do get lost in Spain, it just takes another generation to do so.
Here's a family tree to illustrate the process. The names have been anglicized and the last names have been reduced to initials for clarity.
Another way to write rules #2 and #3 from above would be:
A consequence of this system is that your siblings, because they have the same mother and father, all share the same two last names. And yes, it is quite common for someone to have two identical surnames, if their grandfathers had the same common surname.
Another consequence is that you can't refer to a nuclear family unit as "the Joneses" or "the Simpsons" in Spain. I suppose you could refer to Tommy, Susie, and their parents in the diagram as "the A____ E____ family", but it's almost never done. And there's really no need because the concept of the nuclear family unit is so fuzzy in Spain.
No one has a middle name in Spain, but it's fairly common to have multiple first names, e.g. Juan Carlos, María José, Luis Miguel, etc. Sometimes these are contracted to names like Majo or Luismi, and some people have two first names but only use one.
When a Spaniard becomes famous, it is quite common, when referring to the person, to drop the most common of the two surnames.
I'm not sure if this is done mainly to avoid confusing non-Spaniards with all the names or if it is just to shorten things because famous people are talked about a lot. I suspect the latter.
And there you have it! I hope that you agree that this Spanish system is different but not necessarily better or worse than what you are accustomed to.