Who does Sasuke swear to kill in naruto?

Answer 1

Warning: This WILL give out information you might not want to know if your not far ahead!

In the begining, Sasuke wanted to kill Itachi, his older brother, because he anihilated the Uchiha clan. Then Orochimaru came in the picture and Sasukes was mostly targeting Orochimaru. Eventually, Orochimaru took Sasuke in for care (and by care, I mean Sasuke wanted to be stronger, and Orochimaru gave him this opportunity, and Orochimaru wanted Sasuke to be his next 'vessel', but Sasuke didn't know this until later on.). While in the 'care' of Orochimaru, Sasuke is after Itachi, and secretly after Orochimaru. Orochimaru dies by Sasuke (and dies again by Itachi later on)- and Sasuke makes a team of other ninjas, and goes after Itachi. Itachi dies by Sasuke, and Sasuke finds out the truth of Itachi through Mandara Uchiha (also knows as Tbi, form the Akatsuki). Isntead of going back to the village that Itachi loved so much, and wanted to keep the peace, Mandara drove Sasuke in to a corner (not literally) that made Sasuke turn the opposite directions and target the Leaf village. Why, you wonder? Because the Leaf village wanted Itachi to sacrafice his village to pretty much keep the peace (or something..), and they sacrificed Itachi to do this mission. So now, Itachis after the Hidden Leaf!

Answer 2

Itachi kills Sasuke's parents, and then he says, '' to obtain the mangekyo sharingan, you must kill your closest friend." So volume 27 answers one of the two he swears to kill. But, he swears to kill Itachi, and his closest friend, naruto to obtain the mangekyo. In case you didn't know, Itachi is Sasuke's older brother. n_n