While The Vampire Diaries was full of great and talented actors, many fans will agree that Nina Dobrev's performance on the show was the most memorable. Not only did she end up playing Elena Gilbert, but she also went on to play an additional three characters too, including Amara, Tatia, and popular Vampire Diaries villain, Katherine Pierce.

RELATED: The 8 Best Villains In The Vampire Diaries (& The 7 Worst)

It was the latter that proved to be the most interesting of the lot as Katherine proved to be more dynamic and complex in comparison to the others. No one knew what to expect from her since she was so mysterious and unpredictable. It's probably why fans spend a lot of time researching her backstory and learning what they can about her to see what made her so elusive and how Dobrev managed to emulate her character.

Updated on January 2nd, 2022 by Kayleigh Banks: When it came to The Vampire Diaries, fans should have realized that they should expect the unexpected as nothing was what it seemed. Considering the number of times the main characters had died and come back to life, it shouldn't have come as a great surprise to discover that Katherine had, somehow, managed to become the Queen of Hell and had an army of lackeys at her beck and call.

It appears that, even in death, she is still as elusive as ever but luckily, Nina Dobrev and Julie Plec have done numerous interviews since to help fill in the blanks in her arc and provide some new context. 

Nina Dobrev Carried Two Different Scripts To Get Into Character For Katherine

Katherine standing in a room in The Vampire Diaries

Considering that Nina Dobrev ended up playing four characters on The Vampire Diaries, sometimes two at a time, it's safe to say that she had a lot of preparation to do to get into these characters.

When it came to playing both Katherine and Elena, Dobrev admitted in an interview with Entertainment Weekly [8:00] that she carried two separate scripts because she wanted to "break down what Elena was going through in that episode and what her intentions were, and then having a separate script for what Katherine wanted out of every circumstance." Her dedication and effort certainly paid off as fans can instantly differentiate between the two characters, even when they are on-screen together.  

Julie Plec Hadn't Intended For Nina Dobrev To Play Katherine Aswell

Katherine leaning against a doorway in The Vampire Diaries

In another podcast-like interview (via Entertainment Weekly), Plec revealed that "it didn't occur to [them] originally that Nina should play Elena and Katherine" as the books didn't exactly say that the two looked exactly alike. There was just a resemblance.

However, that soon changed when Plec was approached by an actor who gave them the idea. "I remember Italia Ricci, who had tested for Elena early on, comes up to us at Comic-Con after the show gets picked up [and] she's like, 'I am putting myself in front of you to say I would like to play Katherine Pierce.'" While Ricci probably would have made a great addition to the show, the issue was that the show had already used Dobrev's image for Katherine.

The Reason Katherine Was Killed Off In Season 5

Katherine in flashback wearing green gown in The Vampire Diaries

After spending five years tormenting the Mystic Falls gang, five hundred years running from Klaus, and finally reuniting with her daughter, Katherine was "killed" off in the 100th episode. While she did make several appearances after this, fans might not have realized that Katherine and Elena never shared the screen together after season 5.

Plec revealed that this was because the network was very protective over Dobrev's wellbeing and didn't want her to be participating in long, extensive shoots anymore since it had exhausted her previously. In order for Katherine to appear in the season, they had to virtually say they would kill her off in order to get permission.

Nina Dobrev Had A Lot More Fun Playing Katherine

An image of Katherine standing in the Salvatore Boarding House in The Vampire Diaries

While both Elena and Katherine have proven to be fan-favorite characters in their own right, many fans might be curious as to who Dobrev enjoyed playing the most.

RELATED: 10 Times Damon & Elena Nearly Got Together On The Vampire Diaries (But Didn't)

In the Variety podcast, My Favorite Episode with Michael Schneider, Dobrev seemed to imply that she loved playing Katherine more since the 'period pieces had been a lot of fun to shoot' (via CinemaBlend). The new time setting probably helped the actor to get into character a lot more easily and create such an in-depth villain.

Nina Dobrev Didn't Really Enjoy Wearing The 1800s Outfits Katherine Wore

Stefan and Katherine standing together in Mystic Falls in The Vampire Diaries

While the period episodes did provide some great insight into the backgrounds of Stefan, Damon, Katherine, and some of the ancestors of the Mystic Falls crew, there were just a few downsides when it came to shooting them.

In an interview with Glamour, Dobrev spoke about some of her iconic movie looks (which also included some of Katherine's best outfits on The Vampire Diaries [2:07]). While Dobrev had nothing but praise for the show's costume department and designers, she did say that the corsets and the cages were "uncomfortable" and made it "difficult to breathe."

Nina Dobrev Often Wore Wigs To Differentiate Between Elena and Katherine

Katherine Pierce in Masquerade

Nina Dobrev does have brunette hair in real-life but she actually wore wigs for the majority of the series. Even when her hair was simply worn straight, it was generally a wig. She always wore a wig while playing Katherine. The reason is due to Katherine Pierce's hairstyle being different than Elena's.

RELATED: Why Elena's Vampire Diaries Ending Is Fitting (& Why It Makes No Sense)

This was generally done so that the audience could tell Elena and Katherine apart much easier. Although this could get tricky at times when Elena was impersonating Katherine or vice versa, luckily Dobrev was a talented enough actress to make it obvious who she was playing at any given moment regardless of what her hair looked like.

Katherine's Birthday Is On June 5, Making Her A Gemini

An image of Katherine looking at Elena in The Vampire Diaries

Katherine Pierce was born on June 5 to a wealthy family in Bulgaria. Her birthday makes her astrological sign a Gemini. Considering Gemini is the twin sign, it's very ironic for her to be one considering all the doppelgängers (including Amara, Tatia Petrova, and Elena Gilbert).

Geminis are also said to be duplicitous, although that is not always true of course, for Katherine it certainly is.

Katherine Was Originally German In The Book Series

An image of Katherine looking surprised in The Vampire Diaries

In the book series, the show is based on, Katerina Petrova was actually Katherine von Swartzschild. She came from a German heritage. The reason this was changed in the series is due to the casting of Nina Dobrev.

Nina is actually Bulgarian so the writers decided to change Katherine's background to reflect the actress's real-life lineage. It helped that she was able to speak the language as well.

Katherine's Relationship With Elijah Did Not Exist In The Books

Katherine and Elijah kissing on The Vampire Diaries

Although Katherine had a brief relationship with Elijah, some fans might not be aware that this didn't exist in the novels. The main reason for this is that Elijah doesn't appear in the books and Katherine spent most of her time trying to get revenge against the Salvatore brothers for trying to move on.

While fans were very surprised to see Elijah become one of Katherine's love interests in The Vampire Diaries' fourth season, they were quite disappointed that it had ended so abruptly. When Katherine was attempting to "win" Stefan back, the viewers had watched as she manipulated and hurt anyone who got in the way of that. However, she seemed to be completely different with Elijah and appeared a lot more caring and selfless. It would have been interesting to have seen what storylines they could have created with this dynamic.

Klaus Could Have Used Her To Make Hybrids In The Past

Katherine Pierce turns Caroline on The Vampire Diaries

The reason Katherine gets roped into Klaus Mikaelson's twisted schemes is that he intends to capture her and sacrifice her so he can break the hybrid curse. However, one has to wonder what would have happened had Klaus known that he could use her blood to create hybrids.

RELATED: 9 Things About Caroline That Have Aged Poorly In The Vampire Diaries

At the time, he was only interested in breaking the curse by killing her but had that happened he might not have ever discovered what was possible with her blood. This winds up becoming Elena's problem years later.

Katherine Hated Junk Food At One Point

Katherine Pierce eating a stawberry in The Vampire Diaries.

When we meet Nadia Petrova, Katherine's long-lost daughter, in the show's fifth season, there is one exchange where Nadia wonders why Katherine is eating junk food. She claims that Katherine hates junk food and believed it to be "toxic poison."

This is obviously not true in the series as Katherine is generally shown to have a fondness for sweets and junk. She drinks a lot of alcohol and munches on chips while human. However, it is possible and makes sense that Katherine would have disliked food before being turned since she has always been a fashionista and enjoyed keeping up her modelesque good looks.

Katherine Looks And Acts Physically Different In The Books

An image of Katherine with blonde hair and blue eyes in The Vampire Diaries

The writers had also made a lot of changes to Katherine's physical appearance in the series as the older vampire was meant to have blonde and blue-eyed (like Elena).

RELATED: 8 Things About The Vampire Diaries' Katherine That Have Aged Poorly

Additionally, she had a different personality that was more similar to how Elena behaves in the series while Elena was actually the more fierce of the two. Although Katherine does still play a villain in the books, she is initially described as a "kitten" by Stefan.

Katherine Had More Than One Reason To Take Vervain

An image of Katherine being staked in The Vampire Diaries

It's established early on that Katherine took vervain for centuries because she was on the run from Klaus Mikaelson. The other reason she took it is that she was trying to build up an immunity to it since vervain can be used to weaken vampires.

However, one other reason she might have been using it is to prevent herself from being susceptible to compulsion from Original vampires. Fans don't find out that Originals can compel vampires until the second season but it makes her seem even more intelligent and intent on survival.

Katherine's Relationship With Klaus Is Also Different In The Books

Katherine Pierce and Klaus Mikaelson looking at each other

The book version of Katherine is actually turned into a vampire against her will by Klaus. She becomes very loyal to him and it is under his influence that she becomes increasingly sadistic, cruel, and generally manipulated.

In the television series, Katherine hates Klaus and wants nothing to do with him after he mercilessly slaughters her family for sabotaging his scheme to unlock his full hybrid potential.

Katherine Had A Serious Shoe Obsession

Katherine Pierce in a flashback in The Vampire Diaries.on The Vampire Diaries

Unless fans pay attention to all of Katherine's numerous outfits and accessories, some might not realize that the vampire has a very intense love of shoes.

She's rarely seen wearing the same pair twice and prides herself on being able to do anything she wants while still wearing high heels. Katherine would not be caught wearing sneakers. She often wears designer boots, even when murdering people.

NEXT: The 10 Worst Things That Happened To Bonnie In The Vampire Diaries