Salazar Slytherin is definitely an INTJ who is the founder of the house slytherine. and he pretty obviously lived an INTJ life. - rich, AMBITIOUS, smart, loner, intuitive, powerful, secretive(chamber of secrets lol). and i am pretty sure he wanted and based his house as a mirror reflect of his life. he wanted his students to be just like him (INTJish).
but it didn't-
the house and his descendants didn't live upto his standards except for a few. such as Voldemort, Lucius Malfoy, Bellatrix Lestrange, Barty Crouch, Jr(not sure what his house his). if you read the book and i am pretty sure most of you have you will see that only a few Slytherins were mirror images of Salazar Slytherine.
the rest of them such as Igor Karkaroff, , Vincent Crabbe and Gregory Goyle (and their fathers) etc etc were just stupid bullies (which is definitely not an INTJ trait). they were just proud of being pure bloods and put this macho, high class facade to hide themselves from the rest so that they would not be exposed to be just common wizards just like the muggle borns.
they hated the muggle-borns and considered to be inferior. but they new deep inside that at Hogwarts they were only as smart as the muggle-borns. they were nothing better than the rest.
therefor i must say that the slytherine house was based on INTJ principles (mainly ambition)