Surnames are a different beast compared to given names. In fact, since I don’t often use them much in my writing (they may be mentioned but not often used) I don’t put as much “work” into choosing them.
For surnames I’m more likely to use the suggestions you often read for naming characters, such as looking at the end credits of movies or using the surname of someone I went to elementary school with (not someone I knew well, just a name that I remember well because it was very distinctive). Of course the surname has to be correct for the culture of the character, and in historical fiction the surname needs to be historically accurate (in a certain year they may only have been using “career” surnames or a character living abroad may have a “place” surname). But often characters don’t have a strong cultural heritage (read character is a mutt), and I don’t generally write historical fiction.
In this week’s Character of the Week, however, the surnames were going to be used much more than the given names. For this novel the surnames needed to be interesting, appropriate in feel for soldiers, and distinctive. The writer noticed that four of her characters had names that had the same ending, and that was less than distinctive. They might even have become rhymey, and most certainly would have become annoying.
It’s unfortunate, because the names were all interesting names and would normally have been distinctive choices. But this is the problem with having a strong naming style. Sometimes your style doesn’t work in writing. Sometimes you have to be willing to bend.
Just like I do. I have characters with the surnames Johnson and Jansen in my WIP, and one of them is going to have to go. Johnson is staying, because the character is very “white bread” and needs a common and dull name. Jansen is going to change as soon as I find a better choice for this friend with a heart of gold and her kind parents; and, frankly, the friend deserves better than what she was given originally.
How important your characters’ surnames are will be based on how often they are used, how important the character is in the story, and on whether the character even needs a surname at all. Recently I was reflecting that all writing leaves something of the story to the readers’ imaginations—and the characters’ surnames could be one of those details that the reader doesn’t need to “know” in order for them to know the character.
Consider carefully your character and your writing, and chose the surnames that feel right to you.