Real-World Mythology
Faeries (fae/fay/fey/fair folk/fairies) are mythological beings found in the folklore of many cultures. Unlike many other legendary creatures, there are few commonalities among these stories, as they originated across disparate sources. Instead, the stories are often lumped together with the idea that "fae" is an umbrella term for many different types of creatures—from sprites, pixies, and brownies to leprechauns, trolls, and sometimes elves—that have a human appearance, magical powers, and often exhibit mischievous personalities.
Some stories portray faeries as tiny, and others are human-sized. Some can change their size at will, and others can take on the form of an animal or disguise their appearance with magic. Modern portrayals often give faeries wings, but the original folklore was more likely to give them the power of flight through magic rather than body extensions (if they had that power at all).
Along with wings, modern depictions tend to show faeries as beautiful, cute, and not-at-all scary, so people today often don't interpret their presence in stories as truly dangerous. However, throughout history, faeries were the top creature of myth to be feared, as they could be everywhere and anyone. The whole genre of fairy tales reflects their immense (often malicious) power, even though over time, the antagonists of the tales were relabeled sorcerers or enchantresses.
Because of their reputation, whenever people encountered bad luck (from losing an item to a seriously-ill child), faeries were often blamed, and people would try to figure out how they might have offended the creatures. Thus many beliefs related to faeries revolved around the idea of how humans could avoid offending the local fae folk, such as staying away from certain locations that were thought to be faerie haunts, paths, or gathering circles. Or humans might wear charms, like four-leaf clovers, to protect themselves from fae tricks, or use iron for protection.
Another common belief was that if a human knew the name of a particular faerie, they could summon the being and force them to do as they wanted, due to names having power. The well-known story of Rumpelstiltskin is an illustration of this idea. Some believed faeries' penchant for trickery came from their inability to lie and thus relied on twisting their words to hide the truth, especially when they would otherwise be held to keep a promise.
Other beliefs found throughout history include the idea that faeries were of angelic origin, guiding the processes of nature, such as the growth of plants. These beliefs focused on faeries as nature spirits or elementals, which are magical beings who embody one of the forces of nature and can exert power over that force.
The Story within Ironclad Devotion
The stories of the Mythos Legacy series take our real-world mythology and explore how they would apply to the beings if they really existed—but were hidden among us. In addition, these Mythos beings have their own storytelling legends, such as the source of their magical power (How could faeries make their elemental magic stronger?).
Many of the ideas mentioned above, from the avoidance of iron to the power of specific names, are echoed in Ironclad Devotion, and going along with the idea that faeries are extremely dangerous and not cute, these are human-sized beings with a long history of warfare (and sometimes outright genocide) and no wings. However, some ideas from the faerie folktales have been changed quite a bit for the story, such as using the term changeling to refer to their power to change their appearance rather than of child abduction.
Also, instead of using the well-known Scottish legends of the Seelie and Unseelie Courts for worldbuilding, this story expands the ideas of elemental faeries into clans of the four classical elements of nature (earth, wind, fire, water). Each clan has slightly different magical powers and roles in their society, and the spirits of nature (along with faerie circles for each clan spirit) are important in the overall story.
Just like any human, mythological beings need vulnerabilities for storytelling (especially as they increase in power), so while it's never stated that these fae can't lie, they seem to deflect with a different truth when others might just lie in their place (especially as they are held to the power of a promise through an unbreakable magical bond), but they also have the ability to force humans to speak the truth to them as well. Most importantly, the danger of iron and the power of a faerie's true name are both emphasized and used against them in the story. In fact, as a faerie princess of the fire clan, the heroine of this story is so powerful that a man of iron who knows her true name might be the only human who could match her strength. *grin*
