Minerva McGonagall was the Transfiguration professor and Deputy Headmistress at Hogwarts for over forty years, and a powerful witch and Animagus (PS1, PS4). McGonagall has a stern exterior, keeping her classes strictly controlled and following the rules closely (PS8), yet has a warm heart and cares deeply for her friends and students. She also played a vital role in the Order of the Phoenix, valiantly directing the final battle against Voldemort (DH31). Professor McGonagall has dark hair which she pulls into a bun, wears glasses (PS1), and is frequently dressed in tartan plaids (PS14).
McGonagall was the head of Gryffindor House during Harry’s years at Hogwarts (PS8) and was known for teaching challenging classes (CS6). She did not break rules (PA8) or tolerate misbehavior (CS5, PA14). She also refused to favor her own house (PS8); however, McGonagall cared deeply about Gryffindor’s success (PA10). She cried when Gryffindor won the Quidditch Cup (PA15).
Underneath her stern exterior, it was always clear that McGonagall cared deeply for her students. Her first instinct was to protect them at all times (OP27, DH30), and she could become quite emotional when they were hurt (CS16). Even at Voldemort’s first defeat she did not celebrate, but instead mourned at the passing of James and Lily (PS1), both of whom were her all-time favorite students (PmP). McGonagall often got emotional over Harry’s safety in particular (GF20); she was proud to have him in her house (DH30) and was one of those who cried loudest when she believed him dead (DH36).
Though generally respectful of her fellow teachers, McGonagall had little patience for less competent colleagues. A sarcastic wit came out, for instance, in talking with Lockhart (CS16) or Trelawney (PA11); though she was willing to defend even Trelawney (OP26) – and lead the school in revolt (OP30) – when faced with Dolores Umbridge. She is a tough woman; McGonagall took four stunning spells to the chest and survived (OP31), although she walked with a walking stick for awhile afterwards (OP38).
Minerva was not a member of the Order of the Phoenix during Voldemort’s first rise to power. However, she used her talent as an animagus to help spy on death eaters, providing vital information to the aurors of the Ministry of Magic. By the second Wizarding War McGonagall believed the Ministry to be corrupt and dangerous, so did not spy for them. She became a fully fledged member of the Order after Dumbledore’s death. (PmP).
McGonagall had a great admiration and trust for Albus Dumbledore (PS1), passionately defending him (GF36) and being more than willing to fight on his behalf (OP27). When he was gone, McGonagall stepped up to fill his shoes; she drove Snape from Hogwarts (DH30) and, completely trusting Harry’s instructions, willingly led the school in the Battle against Voldemort (DH31) – even dueling Voldemort herself as the battle drew to a close (DH36). She was also one of the first to rush to Harry upon Voldemort’s defeat, symbolic of the important place she held both in his life and in the wizarding world (DH36).
McGonagall is the Headmistress of Hogwarts by the time of the events of CC.
Minerva McGonagall is an Animagus, able to turn into a cat with markings around the eyes, similar to her square spectacles (PS1). Her Patronus is also a cat (DH30). She traditionally performs the Sorting ceremony at the Welcoming Feast (PS7, CS5, GF12, OP11).
Birthdate: October 4 (JKR).
Birthyear: approximately 1925 (Sch2).
Father: Reverend Robert McGonagall (Muggle)
Mother: Isobel Ross (Witch)
Brothers: Malcolm McGonagall, Robert McGonagall Jr. (Wizards)
Hair: Black, pulled back into a bun (PS7).
Eyes: Square glasses, beady eyes.
Distinguishing features: rarely smiles (PS8); she wears tartan plaids -- even her nightdress and dress robes are tartan.
Animagus: a tabby cat with square markings around its eyes (PS1).
Patronus: a tabby cat with spectacle eye markings (DH30).
Hogwarts: Transfiguration Professor 1956-1998; Deputy Headmistress 1991-1998; Headmistress unknown-2020 (CC).
House: Gryffindor (c. 1937-44); Head of Gryffindor 1991-1998.
Office: First floor (up the main staircase, down a corridor).
Affiliation: Member of the Order of the Phoenix.
Interests: She is very keen on Quidditch and before an injury was a member of the Gryffindor Quidditch Team.
Needlework, correcting articles in Transfiguration Today, watching Quidditch, supporting the Montrose Magpies (Pm)
Minerva was the Roman goddess of wisdom.
The surname McGonagall comes from poet Sir William Topaz McGonagall (Pm).
From the Web
Writing by J.K. Rowling on Pottermore: Minerva McGonagall