The Macmillan Family

The Macmillan family is an ancient and prominent pure-blood wizarding family. They are officially recognized as one of the Sacred Twenty-Eight, a list of families considered to be the most “truly” pure-blood by the 1930s. Their lineage is said to span at least nine generations of witches and wizards. The most notable member of the family featured in the series is Ernie Macmillan, a Hufflepuff student in Harry Potter's year at Hogwarts School of Witchcraft and Wizardry.

The Macmillan family's long and uninterrupted magical heritage grants them a high status within the wizarding community, particularly among those who value blood purity.

• Pure-Blood Lineage: The family's pure-blood status is a point of pride, as articulated by Ernie Macmillan. In his sixth year, he boasted, “I’m a pure-blood, and what’s more, I can trace my family back through nine generations of witches and wizards.” This indicates a well-documented and long-standing magical ancestry.
• The Sacred Twenty-Eight: The family's inclusion in the Pure-Blood Directory's list of the Sacred Twenty-Eight solidifies their historical standing as a core pure-blood family in Britain (Pottermore).
• Connection to the Black Family: The Macmillans are connected by marriage to another ancient and noble pure-blood family, the Black family. This connection further underscores their place within the magical aristocracy.

Ernie Macmillan is the primary member of the family seen throughout the Harry Potter series. He is characterized as being somewhat pompous and a stickler for rules, but also fundamentally decent, brave, and loyal to his friends and school.

• Hogwarts Years:
  • A contemporary of Harry Potter's, Ernie was sorted into Hufflepuff house.
  • In his second year, he initially suspected Harry of being the Heir of Slytherin but publicly and sincerely apologized after Hermione Granger was petrified, realizing Harry would never harm his friends.
  • During the Triwizard Tournament, he supported fellow Hufflepuff Cedric Diggory but was one of the few who did not harass Harry.
  • He became a Hufflepuff prefect in his fifth year alongside Hannah Abbott.
  • He was a firm believer in Harry and Albus Dumbledore's claims about the return of Lord Voldemort and was one of the first to join Dumbledore's Army. His Patronus Charm produces a Patronus in the form of a boar.
  • During the Battle of Hogwarts, Ernie fought bravely against the Death Eaters. He, along with Luna Lovegood and Seamus Finnigan, aided Harry, Ron, and Hermione by casting their Patronuses to drive away a group of Dementors.

Melania Macmillan was a witch from the Macmillan family who married into the Black family. Her name appears on the Black Family Tree tapestry as the wife of Arcturus Black I. They had at least two children, a daughter named Lucretia (who married Ignatius Prewett) and a son named Orion, who would become the father of Sirius Black and Regulus Black. Her marriage into the Black family is another testament to the Macmillan's respected pure-blood status. (J.K. Rowling's Black Family Tree drawing).

• The information that the Macmillan family is one of the Sacred Twenty-Eight was first published by J.K. Rowling on the Pottermore website.
• The existence and details of Melania Macmillan are known from a detailed version of the Black Family Tree hand-drawn by J.K. Rowling for a charity auction. This drawing was later used to create the prop seen in the film adaptation of Harry Potter and the Order of the Phoenix.