The House of Black was one of the oldest, wealthiest, and most powerful pure-blood wizarding families in Great Britain. Their history is steeped in an fanatical belief in pure-blood superiority, a value system encapsulated by their family motto, Toujours Pur (“Always Pure”). This ideology led them to practice the Dark Arts and to hold Muggles, Muggle-borns, werewolves, and other non-human magical beings in contempt. The family maintained its blood purity through strategic marriages with other prominent pure-blood families, such as the Malfoys and Lestranges. Any family member who disagreed with their supremacist views or associated with those deemed “unworthy”—such as Muggles, Muggle-borns, or so-called “blood traitors“—was promptly disowned and literally blasted off the family tree. The Black Family Tapestry, a magical artifact located at Number Twelve, Grimmauld Place, shows these disownments as charred, black burn marks over the names of the exiled. During the First Wizarding War and Second Wizarding War, many members of the House of Black were enthusiastic supporters of Lord Voldemort, with several, including Bellatrix Lestrange and Regulus Arcturus Black, becoming Death Eaters. The family line ultimately came to an end with the deaths of its last two male heirs, Sirius Black and his younger brother, Regulus Arcturus Black. Upon Sirius's death, all remaining Black family possessions, including Number Twelve, Grimmauld Place and the house-elf Kreacher, were passed to his godson, Harry Potter.
The legacy of the House of Black is a significant undercurrent throughout the series, primarily through the actions of its last members and the use of its ancestral home.