It was a very specific set of circumstances. Because Snape asked Voldemort to spare Lily, Voldemort offered to spare Lily if she stepped aside. Voldemort was planning to spare Lily, but Lily asked Voldemort to kill her instead of Harry. Without those very specific circumstances, the love sacrifice wouldn’t have worked. Dumbledore did understand what happened though, and Voldemort described it as old magic, so presumably love sacrifices have happened on rare occasions in the past, but not involving the killing curse.

One that we know of.

This is an interesting thought, i'll rant to my friends about it later.

That’s not why he was saved. Lily’s love for Harry are what protect Harry from Voldemort physically touching him. It was Harry being accidentally made into a Horcrux but Voldy killing Lily that protected Harry from being killed.

Not exactly.. Harry being a horcrux is why he had to die. Voldemort taking Harrys blood to recreate his body meant Harry had the option to come back, as Voldemort had taken part of the protection into himself, tying Harrys soul to Voldemort in a second way.

Unless you mean as a child.. but Harry only became a horcrux after the curse rebounded and Voldemorts soul shattered- takimg refuge in the only living thing it could find- Harry

I don’t think so. Horcruxes were created by (successfully) murdering someone. Lily’s death did that

That's not it at all. Murdering someone rips the soul- it doesn't create a horcrux. The protection rebounded the killing curse- it wasn't Voldemorts intention to create a horcrux.

Harry wasn’t exactly a horcrux, but he was turned into something similar by accident. Once Lily made her sacrifice, Voldemort was unable to kill Harry and his killing curse rebounded. His other horcruxes kept him alive, but his soul had been so badly damaged from creating all of his horcruxes that the rebounded curse shattered his soul again. A piece of his soul remained in Godric’s hollow while the rest of him fled to Albania. This piece latched onto Harry, and Harry acted like a horcrux until that piece was destroyed years later.

Yes, that is dark, you'd think it would've worked a long time ago. there should've been some witches who loved their children enough to make it powerful enough to stop the killing curse. roeeeeee