A British coroner has closed the case on a 130-year-old London murder mystery, ruling that a skull recently found in a garden belonged to a woman killed in 1879.

West London Coroner Alison Thompson confirmed Tuesday that the skull found in the neighborhood of Richmond was that of Julia Thomas, a wealthy widow who was murdered by her housekeeper very close to the site.

Thompson ruled that Thomas was unlawfully killed and that the cause of death was asphyxiation and head injury....