Ernie Macmillian 1
"Personally, I think this is really important, possibly more important than anything else we'll do this year, even with our O.W.L.s coming up. I, personally, am at a loss to see why the Ministry has foisted such a useless teacher on us at this critical period. Obviously, they are in denial about the return of You-Know-Who..."

- Ernie Macmillian on Dumbledore's Army.

Ernie Macmillian was a Pure-Blood wizard who attended Hogwarts School of Witchcraft and Wizardry from 1991 to 1998, and was Sorted into Hufflepuff House. He was an academically strong student and good friends with Hannah Abbott and Justin Finch-Fletchley. In 1992, Ernie initially suspected that Harry was the Heir of Slytherin during the opening of the Chamber of Secrets in his Second Year, and was upset when Justin was Petrified, though he eventually learned the truth. In his fifth year, Ernie became a member of Dumbledore's Army, an organisation found and led by Harry for the purposes of learning practical defensive magic. He joined the D.A again when it was re-instated during his seventh year, opposing Death Eater control of Hogwarts and fighting in the Battle of Hogwarts in 1998. His life after the Second Wizarding War is unknown.

Basic informationEdit

Biographical information

Born: Between 21st April and 1st September 1980.

Blood Status: Pure-Blood

Title (s) : Prefect

Physical information

Species: Human

Gender: Male

Hair Colour: Blonde

Family information

Family members:

  • Melania Black nee Macmillian (Sister to one of Ernie's Ancestors - Deceased)
  • Arcturus Black lll (Brother-in-law to one of Ernie's Ancestors - Deceased)
  • Mr.Macmillian (Father)
  • Nine potential generations of witches and warlocks (Paternal grandmothers and grandfathers - Deceased)
  • Mrs.Macmillian (Mother)
  • Nine potential generations of witches and warlocks (Paternal grandmothers and grandfathers - Deceased)

Magical characteristics

Boggart: Lord Voldemort

Patronus: A Boar


House: Hufflepuff


  • Hufflepuff
  • Hogwarts School of Witchcraft and Wizardry
  • Dumbledore's Army
  • Macmillian Family


Early lifeEdit

" case you're getting ideas, I might tell you that you can trace my family back through nine generations of witches and warlocks and my blood's as pure as anyone's..."

- Ernie yelling at Harry Potter during the Chamber of Secrets incident.

Ernie was born to a Pure-Blood Family that can trace its lineage back nine generations; he may be related to Melania Black nee Macmillian, Sirius Black's paternal grandmother, a Pure-Blood family, which references to both his surname and blood heritage. Although he is proud of his blood status, Ernie is not prejudiced against those of other blood statuses, befriending and looking out for Justin Finch-Fletchley, a Muggle-Born.

Education at HogwartsEdit

First yearEdit

Ernie macmillian 2

Ernie Macmillian talking about Harry Potter to Hannah Abbott in his second year.

Ernie began attending Hogwarts School of Witchcraft and Wizardry on the 1st September 1991. He was Sorted into the house of Hufflepuff, which values characteristics such as loyalty and friendship, during the Welcoming Feast, and soon became friends with fellow Hufflepuff students Hannah Abbott, Susan Bones and Justin Finch-Fletchley.

Second year.Edit

"Hannah, he's a Parselmouth. Everyone knows that's the mark of a dark wizard. Have you every heard of a decent one who can talk to snakes? They called Slytherin himself "Serpent Tongue"."

- Ernie discussing Harry with Hannah Abbott

Ernie with Justin, Hermione and Dean

Ernie with Justin Finch-Fletchley, Hermione Granger and Dean Thomas in 1992.

Hannah Abbott 13

Ernie with Hannah and other Hufflepuffs in 1992.

During his second year, Ernie came to believe that Harry Potter was the Heir of Slytherin after he spoke Parseltongue in front of the Duelling Club. Harry was trying to stop the snake conjured by Draco Malfoy from attacking Justin, but Ernie percieved it differently, believing that Harry was in fact urging the snake to attack. He stepped in to protect his friend urging him to hide in their Common Room. He went into discussion with the other Hufflepuffs regarding if Harry was the Heir of Slytherin, considering the coincidences with the victims. He voiced that being a Parseltongue was the very symbol of a dark wizard and is probably the reason why Voldemort wanted to kill Harry; he didn't want another dark lord competing against him. All the while, Harry, who was attempting to explain to Justin what really happened, was eavesdropping on their conversation and attempted to convince Ernie that the altercation at the Duelling Club was not what it seemed. When it seemed that their argument was going nowhere, as Ernie cited that Harry hated his Muggle relatives, the latter left the library.

Hannah with Ernie 1

Hannah and Ernie at the Duelling Club

Hannah and Ernie pic, with Justin in background

Hannah and Ernie in Transfiguration in their second year, with Justin Finch-Fletchley in background

Soon enough, Ernie's fears worsened when Justin was Petrified. He discussed the matter with their mutual friend, Hannah, who was initially sceptical because she though Harry was nice, but was eventually persuaded to Ernie's point of view.

However, Hermione Granger, one of Harry's best friends, was later Petrified as well. This made Ernie realise that Harry could not be the Heir of Slytherin, as he knew Harry would never harm Hermione, and he gave Harry a public apology. He believed that Malfoy could be the culprit, but Harry gave an emotionless no, making Ernie and Hannah stare.

Third year.Edit

In his third year, Ernie took many subjects similiar to Hermione. He once told Ron Weasley that she had never missed a Muggle Studies lesson, despite having another class at exactly the same time that she also attended. This was due to Hermione's use of a Time-Turner to attend all her lessons.

Fourth year.Edit

Hannah Abbott 5

Hannah and Ernie Macmillian show their 'Support Cedric' Badges to Harry Potter

In the summer of 1994, Ernie and his family attended the Quidditch World Cup final between Ireland and Bulgaria. Whilst there, a Death Eater raid ensued, resulting in chaos amongst those attending.

Ernie's fourth year held place to the Triwizard Tournament, which was hosted at Hogwarts that year, he supported fellow Hufflepuff Cedric Diggory when he qualified and again stopped speaking to Harry Potter, who also qualified, but underage, as he was one of many students who initially believed that Harry had entered himself into the tournament in a bid for further glory. He tried to convince friends in Hufflepuff to agree with him, but they needed not much convincing.

Hannah with Ernie

Hannah with Ernie and other Hufflepuffs in 1994.

Hannah and Ernie 2

Hannah and Ernie revising in their fourth year

"Hey listen, about the badges, i've asked them not to wear them"

- Cedric Diggory to Harry regarding Hufflepuff's wearing "POTTER STINKS" badges.

He also wore a Support Cedric Diggory / Potter Stinks badge. After the tournament came to a close, Cedric Diggory was murdered by Lord Voldemort, coming as a shock to all students and staff members. Cedric Diggory was a member of Hufflepuff and since Harry was with him when he died, Ernie appeared to have forgetten any ill wishes he thought of Harry, and believed his claims to Voldemort returning whilst the Ministry didn't.
Picture 8

Ernie with Cedric Diggory

Fifth year.Edit

"I'm doing eight. Eight or nine. I'm getting an hour in before breakfast everyday. Eight's my average. I can do ten on a good weekend day. I did nine and a half on Monday. Not so good on Tuesday - only seven and a quarter. Then on Wednesday..."

- Ernie talking about studying for his O.W.L.s

Picture three

Ernie in his fifth year questioning Harry Potter about Potions.

In 1995, Ernie became a Hufflepuff Prefect, alongside Hannah Abbott. Unlike previous years, during which he had thought ill of Harry for certain acts he believed him to have committed, Ernie was one of the few Hogwarts students who believed Harry's story that Lord Voldemort had returned. He even went as far as to make an openly public declaration of support on Harry's behalf.

Shortly after the beginning of term, Ernie joined Dumbledore's Army, because of his belief in Harry and of his dismay with Dolores Umbridge, a Ministry of Magic employee who became Defence Against the Dark Arts professor but refused to teach students any practial defence. Ernie believed Dumbledore's Army to be one of the most important things they would be doing that year - apart from O.W.L.s. In the run-up to his exams, he would study between eight and ten hours a day. He developed the irritating habit of boasting about this fact, then inquiring about other students study habits.

After term had ended, Ernie was one of the members of the D.A who helped foil an ambush on Harry by Draco Malfoy, Gregory Goyle and Vincent Crabbe on the Hogwarts Express.

Sixth year.Edit

Picture 4

Ernie at Hogwarts

Ernie: "Harry! We heard a noise and someone said something about the Dark Mark-"

Harry: "Out of the way!"

- Ernie witnessing Harry chase Snape and Draco.

Ernie's hard work and determination from the previous year paid off, as he was the only Hufflepuff student in his year who returned for N.E.W.T Level Potions, earning at least an "Exceeds Expectations" in his O.W.L, something bery hard to achieve claimed Severus Snape, Ernie had also qualified for N.E.W.T level Defence Against the Dark Arts, even with Dolores Umbridge as his teacher.

Later in the year, Death Eaters invaded Hogwarts. Dumbledore's Army was called to battle and the Battle of the Astronomy Tower broke out. It is likely Ernie never recieved his D.A signal, as he had left the Hufflepuff Common Room to investigate a disturbance he had heard when he saw Draco Malfoy, Severus Snape and Harry Potter running down a corridor. He asked Harry what was going on, but got no response. He would later discover that Albus Dumbledore had been killed that night by Snape, and then presumably attended his funeral several days later to pay his respects.

Seventh year.Edit

Picture 5

Ernie in the Great Hall

Professor McGonagall: "Prefects, when I give the word, you will organise your house and take your charges in an orderly fashion to the evacuation point."

Ernie: "And what if we want to stay and fight?"

- Minerva McGonagall and Ernie shortly before the Battle of Hogwarts.

As a Pure-Blood, Ernie was able to return to Hogwarts for the 1997-1998 school year after the Ministry of Magic fell under Lord Voldemort's control; indeed Hogwarts attendance became mandatory. Presumably, Ernie's Muggle-Born friend Justin Finch-Fletchley was not able to come back to school, though Hannah Abbott returned. The two joined the revived Dumbledore's Army, which was led by Neville Longbottom, Ginny Weasley and Luna Lovegood in the absence of Harry Potter, Hermione Granger and Ron Weasley, who were off hunting down Voldemort's Horcruxes. The D.A members apposed the Anti-Muggle propaganda and Dark Arts taught by Death Eater professors Alecto and Amycus Carrow. They painted rebellious phrases on the walls and freed students from detention, where they faced beatings and even the Cruciatus Curse.

Battle of Hogwarts.Edit

On the 2nd May, 1998, Harry, Ron and Hermione returned to Hogwarts as Voldemort approached with his army. A
Picture 6

Ernie stood behind Cho Chang and Padma Patil

meeting was held in the Great Hall, and when Professor McGonagall laid out the plans to evacuate the younger students from the school, Ernie indicated his willingness to fight against the Death Eaters by directly asking Mcgonagall about those who wished to remain behind. His question was applauded by a nember of students who held similiar feelings.

During the subsequent battle, Ernie, along with Luna Lovegood and Seamus Finnigan, came to the aid of Harry, Hermione and Ron by using their Patronuses to drive off a group of Dementors. Ernie's Patronus took the form of a boar.

Later life.Edit

As he was not mentioned among the casualities, Ernie likely survived the Second Wizarding War. His life after Hogwarts is unknown.

Physical appearance.Edit

Picture 7

Ernie Macmillian

"I must say, I'm looking forward to seeing Malfoy's Mother's face when he gets off the train."

- Ernie shortly after helping Harry Potter curse Draco Malfoy, Vincent Crabbe and Gregory Goyle on the Hogwarts Express in 1996.

Ernie Macmillian was described to be a stout-looking boy with blondish hair. When concentrating, such as during Apparation lessons, his face would go a deep shade of pink.

Personality and Traits.Edit

Although others percieved Ernie as pompous, he was loyal to his friends and always honest. He was never afraid to speak his mind, and could readily admit when he was wrong. As a student, he was hard-working and strived to get good marks, which was apparently evident in his fifth year, when he claimied to be revising for his O.W.L.s around nine hours a day. He also displayed great bravery and and loyalty in his participation in the Battle of Hogwarts.

Ernie did however, seem to have a habit of jumping to conclusions regarding Harry Potter; in his second year, he believed and ultimately spread a rumour that Harry was the Heir of Slytherin. During his fourth year, Ernie made his disapproval of Harry's participation in the Triwizard Tournament as a illegal fourth champion clear, claiming Harry had done it to steal the spotlight from Hufflepuff.

Despite being a Pure-Blood and proud of it, Ernie never displayed any prejedice towards those of different blood status as many other Pure-Bloods did. In fact, his two closest friends at Hogwarts were a Muggle-Born, Justin Finch-Fletchley, and a Half-Blood, Hannah Abbott, and he looked out for both of them throughout his studies. Ernie was also one of the first to openly express his support of Harry and Albus Dumbledore during the Ministry's smear campaign again them.

Magicial abilities and skills.Edit

  • Potioneer: With either an Outstanding or an Exceeds Expectations in his Potions O.W.L, Ernie Macmillian was the only Hufflepuff student who continued to N.E.W.T. Level.
  • Charms: Whilst Ernie's true ability in this department is unknown, during the Battle of Hogwarts in his seventh year, he was able to conjure a Patronus in the form of a boar and so must have been at least moderately talented at it.


Hannah AbbottEdit

Hannah abbott 12

Hannah with her friend, Ernie.

Ernie and Hannah Abbott were close friends during their time at Hogwarts, they both had been sorted into the house of Hufflepuff. They discussed the possibility of Harry being the Heir of Slytherin together during their second year, and Hannah appeared easily influenced by Ernie's opinion. Both Hannah and Ernie shared the hobby of collecting Chocolate Frog Cards. They both also strongly supported Cedric Diggory as the School Champion during the Triwizard Tournament, and in 1995, they both became the Hufflepuff Prefects in their year.

Justin Finch-FletchleyEdit

Picture 9

Justin Finch-Fletchley

Ernie's other closest friend was Justin Finch-Fletchley. During the Duelling Club in 1992, he moved to protect his friend when it seemed that Harry Potter was encouraging a snake to attack him. Believing Harry to be the Heir of Slytherin, and that Justin was his next target, he told Justin to hide in the dormitories. When Justin later turned up Petrified, Ernie was very upset and angry with Harry until convinced that he was not the culprit behind the attack on his friend.

Harry Potter.Edit

Picture 10

Harry Potter

During the Chamber of Secrets affair, Ernie held the suspicion that Harry Potter was the Heir of Slytherin when he saw him speak Parseltongue to a snake during the Duelling Club, and believed he was encouraging it to attack Justin Finch-Fletchley. His suspicions were raised when Justin became the next victim of "Slytherin's Monster". However, when Hermione Granger suffered the same fate, Ernie realised that it could not be Harry since he would never harm one of his best friends. To make amends, Ernie gave Harry a public apology.

Despite generally getting along well, Ernie did follow the lead of his fellow Hufflepuff housemates and gave Harry the cold shoulder when he was selected as as the fourth Triwizard Champion in 1994. Since Cedric Diggory had been the chosen Hogwarts Champion, he felt, like many others in the school, that Harry was taking away Hufflepuff's chance for honour and glory. However, with the tragic events surrounding the Third Task, Ernie believed Harry's story that Lord Voldemort had returned and publicly proclaimed his support despite the Ministry of Magic and the Daily Prophet calling him a liar. Ernie's support of Harry was so strong that he was a staunch supporter of Dumbledore's Army, and led the call to arms during the meeting of students in the Great Hall prior to the Battle of Hogwarts.


Ernie is a short form of the word, Ernest, which is derived from the German word ernst, meaning "honest" or "trustworthy", or eornost, meaning "serious". It is the name of the main character in Oscar Wilde's The Importance of Being Earnest. Ernie could also be named after J.K. Rowling's paternal grandfather, Ernie Rowling.

Behind the scenes.Edit

  • Pic 12

    Louis Doyle

    Pic 13

    Jamie Marks

    Ernie Macmillian is portrayed by Louis Doyle in the film adaptations of Harry Potter and the Chamber of Secrets and Harry Potter and the Goblet of Fire. Louis also provided for voice for Ernie for the video game adaptation of Harry Potter and the Order of the Phoenix. Ernie is portrayed by Jamie Marks in Harry Potter and the Deathly Hallows: Part Two.
  • Ernie was born between April 21st and September 1st, as like Harry Potter and Draco Malfoy, he was unable to take the Apparation test with the rest of his Sixth year class, due to not yet being of-age.
  • Ernie's last name was misspelt in the closing credits of Harry Potter and the Chamber of Secrets, as "MacMillan", but was corrected for Harry Potter and the Goblet of Fire.
  • In Harry Potter and the Prisoner of Azkaban, Ernie's last name is misspelt as McMillan.
  • Ernie Macmillian once borrowed Quidditch Through the Ages from the Hogwarts Library, and was due to return the book on 12th August.


  • Harry Potter and the Philosopher's Stone (Book - First mentioned)
  • Harry Potter and the Chamber of Secrets (Book - First Appearance)
  • Harry Potter and the Chamber of Secrets (Film)
  • Harry Potter and the Prisoner of Azkaban (Book - mentioned only)
  • Harry Potter and the Goblet of Fire (Book)
  • Harry Potter and the Goblet of Fire (Film)
  • Harry Potter and the Goblet of Fire (Video game - Appears on a collectible card)
  • Harry Potter and the Order of the Phoenix (Book)
  • Harry Potter and the Order of the Phoenix (Film - Name appears on parchment)
  • Harry Potter and the Order of the Phoenix (Video game)
  • Harry Potter and the Half-Blood Prince (Book)
  • Lego Harry Potter: Years 1-4
  • Harry Potter and the Deathly Hallows (Book)
  • Harry Potter and the Deathly Hallows: Part Two
  • Quidditch Through the Ages.

Notes and references

Harry Potter and the Half-Blood Prince (Book) - Based on Ernie's attendance in Potions, on April 21st, 1997, with Harry Potter and Draco Malfoy when all students currently of age were taking their Apparation tests.

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