SOLVED. YA revolution fantasy where three people are starting an uprising separately from each other but keep getting mistaken for the same person *spoilers*

[Korey]

I read the book in (early?) high school so 2009-2012. The three main characters are a spoiled rich girl and her half brother (who is illegitimate I think) and a con artist who crossed there path very early on in the book and then go their separate ways. The girl ends up living with a desert tribe for a while and learns their magic, which they describe as speaking with *element*. Can’t remember what happens with the two guys.
The king gets over thrown I think and all three get dragged into the fight and saving people. There’s some legend about a guy and in order to get people to listen to them they use that name without realizing other people are using it as well. All their actions get attributed to the one person and the legend grows.
Major spoiler- at the end there’s a duel for the kingdom(?) and another random person says he’s the legendary guy and does the fight. After some cheating on the enemy’s side the girl gets so angry she calls down lightening and kills the enemy. There’s an epilogue that’s basically a history book entry where they conclude that the guy guy who claimed to be the legendary characteristic of been because no one ever claimed the name again. (The writer of this entry is the descendant of the con man and is basically a senator and is called a goat herder based on a joke the con man once made).
I’ve been looking for this book for ages and going made scrolling lists trying to find it. I can’t remember is it’s a trilogy or just a really long book. I read it around the same time I read the demon king and graceling.

[Kris]

Korey, I see you moved your thread to a Solved folder and added Fall of a Kingdom by Hilari Bell to the header/ topic title. Glad you found your book.