I want to have characters who have no family name. I notice that people in Indonesia and Iceland have no family name. What kind of culture/tradition caused that? Are there any common factors that cause people not to use family names?
Take a look at this question and the answers there. Even though the answers are about not using ANY names at all (simply titles) I believe that it will be a great start for you.
It is difficult to find a commonality for every single culture that doesn't use family surnames, because the naming conventions outside of that all have different flavors and cultural reasoning behind them. Although my top answer for the Q&A I linked to talks a lot about place in society and not being an individual--that's specific to THAT naming system (none at all). That culture would not have much in common where origin place is the name, or clan (which is not always the same as family), or taking a benefactor's name. The list of variations is too long and the reasons for them are as varied as the list (hence the votes to close the question as too broad).
Since you are specifically looking at Icelandic culture, what I have found there is that there is a CHOICE as to last name. That is, the person chooses what they want to be associated with.
Traditionally, instead of a partricharial FAMILY name, your last name comes from your father's first name with --son added on the end. But, as you can see from the wikipedia entry, this has changed as the culture has, and it's all about who you would like to be associated with.
First names are actually strictly monitored in Iceland.
There are just over 330,000 people in Iceland. There are over 8.5 million people in New York, New York, USA.
With so few people their naming convention works.
Indonesia is different because there are more people, however, the population is segmented into lots of islands.
These naming conventions are actually ancient ones. I would say they are left-overs from an earlier time.
Using a family last name wasn't something that was always true, and developed over time--generally because of social custom, but often because of laws adopted by a country to eliminate confusion.
Ireland was the first European country to use fixed family surnames, starting around 900. The gentry in England and other places began using them in the 1000s, and this spread to the common folk, and by 1400 it was common practice.
Use of Family surnames is a relatively NEW thing (in Europe at least), if you look at the history of names and even today is nowhere near universal!
The answer to this question:
What kind of culture/tradition caused that? Is there any common factors that make people don't use family name?
Depends GREATLY on the time period you are addressing. Because prior to the Renaissance, it certainly wasn't that common. Iceland and Indonesia specifically have in common that they want to preserve their naming conventions to preserve culture and tradition. But, as I said different naming traditions have different lines of reasoning.
Romans had names that associated them with a group or kinship rather than surnames as we know them.
In the Middle Ages if you married a higher status person, regardless of gender, you often took their name instead of your own.
I think that you need to look at this question from a different angle. In the history of humanity, having a family surname is actually weirder than not having one. Instead of asking why a culture wouldn't have family surnames, you should be asking why we do.
The answer to that is mainly to make record-keeping and identity easier to track, and had spread over Europe pretty much completely by the 1600s. However, there were often terms in a will that required the changing of your last name. Like if you had an Uncle with a different family name and no heirs with his name, he might make the terms of you receiving his inheritance for you to change your last name to his--this happened with regularity in England in the 1800s and some in the 1900s.
Please do take a look at all the different naming conventions on this wiki link.
Simple, a very small society.
You don't need family names when there are 20 people in your village and everyone knows who you mean when you say "John".
As societies grow you begin to need to distinguish between individuals, there may be four Johns now so you need to be able to tell them apart. You can do this in a variety of ways;
- Some kind of identifying quality; "Big John" (or the somewhat sarcastic "Little John") for someone of abnormal size.
- A profession; "John the Blacksmith".
- Parent's names; "John Williamson" or the more unusual -dottir used in Icelandic names
The issue with all of these is that they eventually evolve into family names that become passed down over time (Little, Big, Smith and many varieties of -son surname all exist today), so you also have to look at other reasons why family names exist.
Another important use of family names is inheritance, when a lord's land passes through closest living relatives in some way or another you need a way to track who those people are. Having family names makes doing so much easier (particularly as in most cultures they seem to pass down the male line like property would have) as you know when Lord Windsor dies you just need to find the oldest male Windsor (depending on the type of inheritance used) and he becomes the new lord.
So, depending on what exactly you want (no family names of any kind, or just no family names like most modern Western cultures use) you probably want to keep your society small and remove issues of inheritance and ownership of property and land.
Historically people didn't have family names. For example, Fred would be Fred son of Bob. This later could be formalised as "Fred Bobson". Also Frieda Peterdottir would be a Scandinavian form of Frieda daughter of Peter. The common factors were initially people didn't need family names. The adoption of family names only became necessary when additional identifying characteristics were needed. Hence family names.
Basically small societies don't need more extensive and better identification types of names. There are no factors determining why people wouldn't have family names. It's more the reverse is true. There were factors to ensure the adoption of family names.
In some societies people would be called the son/daughter of or by their job description John the ferrier, or even by their place of birth or where they lived John from rocky farm.
Mostly in ancient Times people would receive a first name at birth, maybe... and then be called by the parents name or their profession.
In some societies kids would only receive a name after a certain age.
This answer is two separate ideas, the first a warning/hurdle when designing this society, the second a more specific setup of why this society might not have surnames.
In addition to the other answers, one hurdle you must consider in foregoing surnames is potential inbreeding.
I see a lot of people suggesting small societies of a few tens of people, but once you get a few hundreds of people, it becomes possible that no one individual personally knows everyone any more. In a society that is fairly remote and self-sustaining, this can lead to a rather small gene pool and family names are a shorthand to check for immediate relations.
As a very specific example, my mother-in-law hails from a village of 200 people or so, again a remote and self-sustaining place where they didn't see much in the way of travelers, mercantile or otherwise. Similar to Prime's comment to the original question, her last name was very common - easily shared by 50% of the village, and not by mere coincidence.
However, while I like Prime's direction suggesting this redundancy could make a society with meaningless surnames, it rather acted as a warning in this village. Because the name was so common, it was customary for individuals wanting to marry to check back five generations and make sure they weren't too closely related. People who didn't have this ubiquitous surname were actually sought out, and while the five-generation rule still existed, it was a pretty good indication that the two people probably weren't related.
You could still have a small society, but you'd need some other metric to keep potential inbreeding at bay. A sci-fi setting could use a DNA scanner that makes sure people aren't too genetically similar, for example. Low-tech alternatives would be a village-ordained Match Maker, whose sole job is to keep track of people and their lineage and approve/straight up arrange all marriages. Or even making sure your small society has a healthy inflow/outflow of residents would be enough.
One suggestion for a society without surnames is the familial "I am Spartacus" equivalent, where for some particular reason - I'm leaning towards governmental defiance, personally - the entire society has all opted to use the same exact surname. In my example, it could be they're an ethnic minority with a different naming scheme that isn't recognized, but government policy dictates everyone must have a name of some specific format, so in protest the whole society picks the exact same thing. Optionally applies to first names, too, and the whole society has Official Names of "John Smith" used purely in protest, while everyday interactions use the unrecognized names determined by whatever cultural customs you like.
Heck, they could even be the same ethnic group as the rest of the country and just do this while picking intentionally "odd" everyday names purely out of protest for personal identity, and the custom has gone on so long it's become its own cultural/regional thing.
Your characters can be disowned by their families.
If this is a happy little medieval village that is harder to explain. But if you have a society of outcasts, living on the fringe, they can be nameless. When they were cast out, their names stayed behind with their families.
Maybe the entirety of the name stays behind. The outcast person is nameless; no-one. If things go well, they get new names when they join the society of outcasts.
A society made up of small communities. You get a given name and your community is your last name. There is a registrar of some kind for each community that prohibits the use of a first name that matches anyone currently alive in the community.
This does not preclude cities, it's just cities are made up of a group of communities. I do not believe this structure would be stable in the long run with a modern society, though--people move around too much.
One of the only reasons why we have family names in the west is one of the inevitables, in this case Taxes rather than Death. Surnames were used to keep track of what a particular family owned and what they owed for it. Historical sources suggest that most, 90%, of all English Language surnames originate in the UK and that they were mainly taken up/given out in the 11th Century as part of the Norman reorganisation of the British Isles. As such the Scots and Welsh largely didn't have surnames until the 17th Century when it became a legal requirement for those getting married throughout the UK. So a society that is small and untaxed would have no need for surnames to keep track of these things.
Looking at it from a worldbuilding perspective (i.e. "What could cause this in my fictional society?") and not an anthropological one (i.e. "What did cause this in these specific historical instances?"), I'll suggest an expansion on the existing answers.
You need a culture where tracing a family lineage isn't important to the people or to the government. It's been noted above that a big factor that would make it important is inheritance. So the primary way members of a given generation earn their wealth should not be inheriting it from their parents. Perhaps people get buried with all their gold and personal effects when they die. To account for real estate, maybe the cultural norm is that a dead man's land becomes terra nullius instead of passing to his offspring, or the society is nomadic and land ownership doesn't exist.
Depending on the world you're trying to build, another explanation might be that the incidence of armed conflict is so high that most people gain their wealth by conquest, and inheriting your fortune is considered shameful (consider how today "daddy's money" is something of a pejorative). There's no point in tracing the ownership of wealth past a generation or two because it's changed hands so many times. Similarly, any kind of hereditary dynasty doesn't produce more than a couple of rulers before another overthrows it, so even the king doesn't worry about proving his legitimacy by appealing to who begat whom.
As an alternative to inherited surnames in such a society, your characters could earn their descriptors through feats of arms. The humble Bob becomes Robert Cannonbreaker after earning renown for conspicuous bravery when he spiked the guns in a certain battle, for instance. Perhaps the children of a few really legendary individuals use a patronym until they have an impressive accomplishment of their own to boast about. There's all sorts of places you can go with this, but the general flavour of the culture might be something Vikingish.
A real life modern example I've seen in relatively remote East European villages: people do have family names, and they are registered by the state and they are printed on national ID cards, driving licenses, passports, etc. but no one actually uses them. If the same name is used by more people, they are differentiated most often by nicknames. In other cases, by the father's name, or from which part of the village they come from (or if they come from a neighboring village, than by that one).
The real family names are in such disuse, that even relatives or friends don't know them at all, or have to really think hard to recall them.
I think family names culturally come from inheritance (economics), relationships (family) and authority (politics). If am friends with George HW Bush and I know what his political power and economic pull is, then I am more likely to support George W Bush for Governor of Texas and then President of the United States. In smaller societies where people already know everyone's financial, relational and political status, there is no need for family names.
My perspective is, perhaps, somewhat orthogonal to the other responses here: You are a number in the system. Sure, if you insist you can be 'Paul' or whatever when you're among your drinking buddies, but for all purposes "that really matter", you're ID 10568. This makes it trivial for the MCP to manage your affairs.
Now, a lot of the questions that crop up here focus on a (faux-) ancient society, but your question does not rule out a future/dystopian one, so my response is rather Brazil (if I may be allowed to verb that noun).
As a interesting fact, in Finland having a family name became compulsory only in 1920.
Traditionally in Eastern Finland family names were used before the bulk of Europe. In Western Finland, although, not so much.
In Western Finland it was common to person have a given name and a house name, or a military name, if said person had been serving in military servive during the Swedish rule. If a person would move to another house, the house name would be accordingly updated. Military names were, to my understanding, given for life, and somewhat usually passed to next-of-kin.
The use of patronyms was, and somewhat still is, common in both west and east.
So, in pretty homogenous and small group, using such names could differ pretty much.