Macmillan Family

The Macmillan family is a pure-blood wizarding family, noted for its ancient lineage and inclusion in the “Sacred Twenty-Eight”, a list of supposedly true pure-blood families published in the 1930s (Pottermore). The most prominent member of the family featured in the series is Ernie Macmillan, a contemporary of Harry Potter at Hogwarts School of Witchcraft and Wizardry and a staunch member of Hufflepuff house. The family is known for its long history, with at least nine generations of wizards preceding Ernie.

• Ernie Macmillan

Ernie was a Hufflepuff student in Harry Potter's year. Initially pompous and sometimes misguided, he ultimately proved to be a loyal friend and a brave wizard.

• Hogwarts Years
  1. Second Year: Ernie initially suspected Harry of being the Heir of Slytherin, publicly voicing his fears after Justin Finch-Fletchley was petrified by the Basilisk. However, after Hermione Granger was also attacked, he realized his error and offered Harry a heartfelt apology.
  2. Fourth Year: Following the death of Cedric Diggory at the end of the Triwizard Tournament, Ernie was one of the few students who openly and steadfastly believed Harry's account of Lord Voldemort's return. He wore a “Support Cedric Diggory/Potter Stinks” badge but claimed it was to show support for the Hogwarts champion, not to antagonize Harry.
  3. Fifth Year: Ernie became a Hufflepuff prefect alongside Hannah Abbott. He was a vocal opponent of the Ministry's interference at Hogwarts under Dolores Umbridge and was one of the first to join Dumbledore's Army. He expressed great pride in his and Harry's ability to produce corporeal Patronuses.
  4. Sixth & Seventh Year: Ernie continued his studies, taking difficult N.E.W.T.-level classes. During the Battle of Hogwarts, he helped organize the evacuation of younger students before returning to fight against the Death Eaters, last seen helping drive away Dementors from Harry, Ron, and Hermione.
• Personality and Appearance

Ernie is described as a “stout boy” with a somewhat “pompous” and formal manner of speaking. Despite this, he possesses core Hufflepuff traits: he is just, loyal, and has a strong sense of fairness. He is not afraid to admit when he is wrong, as shown by his apology to Harry in their second year. His bravery is undisputed, as he fought in the Battle of Hogwarts.

• Magical Abilities

Ernie was a competent wizard. He passed at least five O.W.L.s with high marks, qualifying him for several N.E.W.T. courses. His most notable magical achievement was his ability to conjure a corporeal Patronus Charm in his fifth year—a significant feat for a student his age. His Patronus takes the form of a boar.

• Melania Macmillan (née Black)

Melania was a member of the noble Black family who married into the Macmillan line. Her name appears on the Black Family Tree tapestry in Number Twelve, Grimmauld Place. Her marriage to a Macmillan further cemented the family's pure-blood credentials and connected them to one of the oldest wizarding clans.

• Ernie's Father

While never named or seen, Ernie's father is mentioned. Ernie proudly states that his family has a long magical history, remarking, “I'm a pure-blood… and my family have been wizards for nine generations.”

The Macmillans are a respected pure-blood family with a long and unbroken line of magical heritage. Ernie's claim of his family being magical for nine generations highlights their deep roots in the wizarding world. Their inclusion in the “Sacred Twenty-Eight” directory confirms their high status among pure-blood purists (Pottermore), though it is unknown if the family itself subscribed to the blood purity ideology as strongly as families like the Malfoys or Blacks. Ernie's own actions, particularly his loyalty to the half-blood Harry Potter and Muggle-born Hermione Granger, suggest a more tolerant view.

• Macmillan: The surname is of Scottish Gaelic origin, derived from MacMhaolain, which means “son of the tonsured one” or “son of the devotee.” This may allude to a follower or disciple, fitting the loyalty and steadfastness characteristic of Hufflepuff house.
• Ernie: A diminutive of Ernest, a name of German origin meaning “serious,” “resolute,” or “battle to the death.” This reflects Ernie's often serious demeanor and his courage during the Battle of Hogwarts.
• Melania: A name of Greek origin meaning “black” or “dark,” a fitting name for a member of the Black family.

• In the film adaptations of the series, Ernie Macmillan was portrayed by actor Louis Doyle.
• The information regarding the “Sacred Twenty-Eight” and the Macmillan family's inclusion on the list was revealed by J.K. Rowling on the Pottermore website and is not mentioned in the original seven novels.