Severus Snape is a highly complex character. He is a favorite of many fans, who believe him to be a tragic figure.
He did, however, present himself as an evil and cruel Professor. Was that fueled only by his character, or was there a reason for his foul behavior?
Considering he was an outcast before attending Hogwarts, and while at school, he was mercilessly bullied by Marauders, his character doesn’t surprise us that much.
However, the choice of friends while at school may fuel more questions about Snape’s allegiances. Was the Potions Professor also a Death Eater?
Was Snape a Death Eater?
Yes, Snape was a Death Eater.
He had the Dark Mark on his left forearm. Professor Karkaroff gave us a hint beforehand, but Snape proves it himself by showing the Mark to Cornelius Fudge at the end of Harry Potter and the Goblet of Fire.
Snape strode forward, past Dumbledore, pulling up the left sleeve of his robes as he went. He stuck out his forearm and showed it to Fudge, who recoiled.
“There,” said Snape harshly. “There. The Dark Mark. (…) Every Death Eater had the sign burned into him by the Dark Lord.”
He also befriended many Death Eaters when he was still at school, and while that doesn’t necessarily mean he was one himself, it points us in that direction.
He also attended Voldemort’s meetings and answered his calls the way only Marked Death Eater would.
When Did Snape Become a Death Eater?
Based on Snape’s memories he shared with Harry, we learned that Snape joined Death Eaters when he was still in school, although without the Dark Mark, and not sworn to Voldemort yet.
The proof comes directly from Lily’s mouth when she accuses Severus of being friends with Death Eaters at the end of their fifth year, after O.W.L. exams.
“You and your precious little Death Eater Friends – you see, you don’t even deny it! (…) You can’t wait to join You-Know-Who, can you?”
But even before that, Lily confronted Snape of hanging out with people who deal with Dark Magic, calling out names, like Avery and Mulciber, who are earlier in the books named active Death Eaters.
Considering that Snape and his Slytherin friends were still at school and couldn’t leave the premises to perform as full-time Death Eaters, we can assume that Voldemort didn’t want them to wear any marks yet, but they thought of themselves as his followers already.
Why Did Snape Become a Death Eater?
From what we learned of Snape throughout the books, we can say that he was a loner from early on, having only one person to talk to, Lily Evans.
The moment he was sorted to Slytherin, he was accepted to a group, his new “family.”
Snape wanted to belong somewhere and be accepted for who he was. His new friends were powerful, and he learned really fast how to protect himself from being bullied. And as Lupin stated in the Order of the Phoenix:
“Snape was a special case. I mean, he never lost an opportunity to curse James.”
He joined Death Eaters to gain more power and to belong somewhere. He probably believed for a time that wizards were superior to Muggles, as he used to call every Muggleborn a “Mudblood.”
Did Snape Kill as a Death Eater?
We believe that the only person Snape ever killed is Dumbledore. We know that every time a wizard kills, his soul gets ripped, damaged somehow. When speaking with Dumbledore about Draco’s soul, Snape insinuates that his soul is not damaged either.
“That boy’s soul is not yet so damaged,” said Dumbledore. “I would not have it ripped apart on my account.”
“And my soul, Dumbledore? Mine?”
Even though he was Dumbledore’s spy at the time, he was still acting as a Death Eater, still possessed the Dark Mark on his left forearm, and therefore we can say that Snape did kill as a Death Eater, even if only this once.
Because of the Dark Mark on Snape’s left forearm, we can say that Snape was a Death Eater throughout the whole series until he died in the Shrieking Shack.
Although, after losing the only person he ever loved, he had a change of heart, and he became a Death Eater only on the outside, performing his duties for Albus Dumbledore.
We assume he did not believe in Voldemort’s beliefs anymore, and he didn’t want to participate in any of the Death Eaters gatherings.