Hogwarts was founded over a thousand years ago by the four greatest witches and wizards of the age. The four school Houses are named after them: Godric Gryffindor, Helga Hufflepuff, Rowena Ravenclaw, and Salazar Slytherin.
“You have used me. I have spied for you, lied for you, put myself in mortal danger for you. Everything was suppose to keep Lily Potter’s son safe. Now you tell me you have been raising him like a pig for slaughter”- Severus Snape