Lost Orphaned Royalty
Villains often try to kill off the whole royal line in their attempts to take the throne. This hardly ever works and they really ought to know better, as a Lost Orphaned Royal will surely turn up sooner or later to take it back. That is this trope. If the orphan in question was lost as a baby or Switched at Birth, that is also this trope. If the orphan was sent away by the King and Queen to be raised by simple peasant folk for what doubtless seemed like a very good reason at the time, that is also this trope. If the orphan was accidentally dropped down the laundry chute by an absent-minded cleaning woman and adopted by a pack of Sewer Gators, that is still this trope. Basically, this trope is when a child raised as an orphan turns out to actually be the next heir to the throne. The orphan may or may not be aware of the situation, and ditto with the reader and the rest of the characters; what matters is that the child was not raised as royalty and was, at some point and by somebody, presumed Lost. For an interesting spin, the orphan could BE the villain, obsessed with getting the life he or she deserves to have, being the true heir and all... Often overlaps with or leads to Really Royalty Reveal, Hidden Backup Prince, Man in the Iron Mask and Rightful King Returns. Suddenly Suitable Suitor is a common plot twist.
- Lone Starr of Spaceballs
- Once Upon a Time has Emma, the child of Snow White - who was Queen for some time before the curse took effect. Emma was sent away as a baby, so she qualifies as Lost, and she was raised as a foster child, so she fits the Orphan part. Technically she's the heir to the throne, but no one seems to have noticed, and it's never brought up.
- Shasta, from C. S. Lewis's The Horse and His Boy is one. He was abducted by an Evil Chancellor, lost in the middle of a naval battle between the Chancellor's forces and the royal navy, and then was taken in by a fisherman. Later he finds his true family and grows into Cor, King of Archenland.
- Jenna from Septimus Heap, even though her father is alive, but virtually nonexistent.
- Discworld: Captain Carrot Ironfoundersson was orphaned as an infant, then raised by dwarves, before eventually travelling to Ankh-Morpork to become a city guard. He turned out in face to be the rightful 'eir to the throne, and from all appearances he'd be damned good at it, what with his essential king-ness meaning the entire city, horrible selfish jerks to a human, actually like him. But he really doesn't want to be king, and the man in charge doesn't want a king, and Sam Vimes, his boss really doesn't want kings. So he isn't the king, and everyone is happy. Well, everyone within reason.
- Aegon Targaryen, a.k.a. the Young Griff, a.k.a. the Walking Spoiler in A Song of Ice and Fire, supposedly an orphan and an adopted son of an exiled knight. The orphan part is completely true, though. He is well aware of who he really is, and his adoptive father is preparing to put him on the throne.
- Slackjaw from Dishonored. He was raised by a whore and the heart reveals that he is actually a prince, but that he'll never know.