Caelia is actually an old rp character from the days of AOL chat room rp (...man that makes me feel old) and I mainly modified her to fit the world. Ness and Karima are vaguely similar, based on characters I had prior that I'm reworking for Eorzea instead of their original world. Personalities are largely the same, motivations, etc.
Lune and Rivienne though are completely original to XIV. Character creation is a dangerous thing! I had been dicking around in character creation while I was getting hit with a string of 90ks, made them and then went "Oh, I like the way these characters turned out!" and then it slowly became "who are they, what are their motivations, where are they from" etc. Rivienne ended up being from Owl's Nest in E Coerthas, chased out by the Calamity who has a scar on her chin from fighting a dragon*. Lune ended up being a misbranded heretic (using the facial tattoos that Hyur females get heh.) I hadn't quite pinned down what had done it (originally it was the fact that her eyes are actually two different shades of blue, but that was kind of special snowflake-y) to the fact that she's actually a dragon who just didn't want to fight, to someone who had been asleep for a long time by some awesome magic, to where it is now (something that actually makes sense according to lore, mainly.) Usually I can get a personality out of that; in Lune's case it was "she's going to be terrified of anyone and everyone because who knows who might be from Ishgard even in the sticks?" Rivi was a little harder but due to her scar and how that one happened, I went with laid back with a decent sense of humor.
Obviously, all of it was expanded on, but tl;dr, I start with the character and their look first, then build on that with their history, then personality. Once I get a good base, I expand and go back and make changes; or if things just seem right for a character (and that does happen!) I don't have to change much, if anything at all and just roll with it.
*Rivienne, as a kid, was playing with her siblings, saving them from a "dragon." She slipped and fell on to some rocks and ripped open her chin. Still saved the younger kids from that "dragon" that they were imagining, and now tells the story for kicks.
Lune and Rivienne though are completely original to XIV. Character creation is a dangerous thing! I had been dicking around in character creation while I was getting hit with a string of 90ks, made them and then went "Oh, I like the way these characters turned out!" and then it slowly became "who are they, what are their motivations, where are they from" etc. Rivienne ended up being from Owl's Nest in E Coerthas, chased out by the Calamity who has a scar on her chin from fighting a dragon*. Lune ended up being a misbranded heretic (using the facial tattoos that Hyur females get heh.) I hadn't quite pinned down what had done it (originally it was the fact that her eyes are actually two different shades of blue, but that was kind of special snowflake-y) to the fact that she's actually a dragon who just didn't want to fight, to someone who had been asleep for a long time by some awesome magic, to where it is now (something that actually makes sense according to lore, mainly.) Usually I can get a personality out of that; in Lune's case it was "she's going to be terrified of anyone and everyone because who knows who might be from Ishgard even in the sticks?" Rivi was a little harder but due to her scar and how that one happened, I went with laid back with a decent sense of humor.
Obviously, all of it was expanded on, but tl;dr, I start with the character and their look first, then build on that with their history, then personality. Once I get a good base, I expand and go back and make changes; or if things just seem right for a character (and that does happen!) I don't have to change much, if anything at all and just roll with it.
*Rivienne, as a kid, was playing with her siblings, saving them from a "dragon." She slipped and fell on to some rocks and ripped open her chin. Still saved the younger kids from that "dragon" that they were imagining, and now tells the story for kicks.