In most of the fantasy stories I've read or heard of, there is usually at least one race of people that live longer than the others. Writers often struggle to come to grips with how this will effect the culture of this people. Here are some tips.

1. A long lived society will naturally be more advanced. People who live over 200 years have the much greater learning period, as well as greater opportunity to oversee the long term development of a project. If one of your races lives over 500 years, you may consider making them more advanced.

2. A long lived society will develop much stronger traditions, and maintain more accurate histories. Strong traditions, of course, may offset the development of technology, or any number of other things.

3. A long lived society will result in a long lived, close knit nation. Incredible opportunities for a story lie here. An empire of this nature could last a millennium.

Also, long lived races tend to reproduce more slowly, so there will be fewer of them than their neighbors, which could also affect development. If a long lived race has one child per couple every fifty years, children would be very important and education would be a very big priority. A disaster in which many of the race die would result in a major set back that could take centuries to recover from.

Armorbearer, the thing to remember is that they're population will be similar to those around because although the may reproduce at a later age than other groups, they also die at a later date. The effects essentially balance themselves out.

It should also be noted that although it may take longer to develop reproductive organs, the rate of reproduction in humanoid creatures will remain similar to people today, because the body of a longer lived people is necessarily healthier, and may conceivably recover faster from a pregnancy that normal humans.

Also, contrary to the beliefs of many, if your race of people lives, say, 1000 years, it will not take longer for a child to develop, provided it's size and brain function are not significantly greater than that of humans. However, you might have the children of this race remain in the womb longer, so they emerge with a more developed body.

Also, you could just entirely disregard science. (Hey, it worked for Tolkien!)

lol. good points. Although, the science of this world doesn't necessarily need to be the same in a book.

This is true, but as a general rule, it's best to either keep science as it is, or to simply not touch on it. As humans, we really understand very little.

I actually consider it part of character development. I have a hard time taking a 2000 year old character seriously if he isn't at least slightly smarter than a normal person.

It's also important to note that although Tolkien's elves were by no means scientifically accurate, they were in no way scientifically extraordinary. (Everything about them was scientifically explainable, although Tolkien cleverly avoids explanations.)

My main issue involving the rate of reproduction is in recovering from a disaster. If half of the population were to die, it would take them much longer to recover than a more prolific race. I'm not saying that they couldn't reproduce quickly, I am mainly basing my opinion on long-lived animals since we don't have any humanoid races that live thousands of years.

Most long lived animals develop their youth at the same rate, if you take into account development inside and outside of the womb. People often don't realize that the longer an animal spends inside the womb, the more developed it is when it is born, and thus, it doesn't spend as much time developing outside of the womb.

Also, I'm pretty sure that there are no animals which have a significantly higher life expectancy, so I'm not sure what exact animals you mean. Would you please explain?

I don't mean animals with a longer life expectancy than Humans, I am more referring to the animals that have the longest lifespans in comparison to the animals with the shorter lifespans. For example, whales, many kinds of whales have been or are endangered because they have been hunted faster than they can reproduce. Smaller animals on the other hand, although short lived, reproduce quickly; and though they are hunted mercilessly by predators, there are still plenty to continue the species. I don't think mice could ever go extinct! That is my reasoning, it may or may not hold true for humanoid races, and one story may agree with my train of thought while another may not. That is why the genre is called Fantasy.