Madam Undersecretary Professor Dolores Jane Umbridge was a half-blood witch and Ministry of Magic bureaucrat who served as Senior Undersecretary to the Minister for Magic under Ministers Cornelius Fudge, Rufus Scrimgeour, and Pius Thicknesse.
In 1995 by order of the Ministry, she was installed as Defence Against the Dark Arts Professor at Hogwarts School of Witchcraft and Wizardry, and then later Hogwarts High Inquisitor and Headmistress of Hogwarts School of Witchcraft and Wizardry, after Professor Albus Dumbledore had been fired. In all three of these positions at Hogwarts she had enormous power over the students, teachers, and the curriculum, which she wielded despotically. Her time at Hogwarts was characterised by cruelty and abusive punishments against students, and because of her interfering and condescending ways, she was generally hated by most students and teachers alike.
After her suspension from these additional posts and the fall of the Ministry of Magic, Umbridge ran the Muggle-Born Registration Commission and sadistically prosecuted many innocent people. After the Second Wizarding War, she was sentenced to Azkaban for her crimes against Muggle-borns.
❝...she drafted an anti-werewolf legislation two years ago that makes it almost impossible for him to get a job.❞ –Sirius Black
sources: harry potter wikia
A/N: Dolores means pain in Latin. She's also clearly inspired by Thatcher.
