Magrat Garlick (pronounced Magg-rat) would have been called Margaret but her mother couldn't spell it properly. Her mother was Simplicity Garlick, her maternal grandmother was Araminta Garlick and her maternal aunt was Yvonnel Garlick. Witches don't pay much attention to the paternal line. Magrat is thin, has a frequently red nose and an unruly mass of frizz and split ends that still awaits a Good Hair Day.
She was the original Maiden in the Lancre Coven, which consisted of herself, Granny Weatherwax and Nanny Ogg. She is often described as "a wet hen", generally by Granny Weatherwax. Magrat believes in crystals, folk wisdom, and cycles of nature, and is overall a gentle parody of New Age pagans. Magrat's gentle personality allows her to mediate between the oft-clashing Granny Weatherwax and Nanny Ogg, though she does occasionally displays a strong temper herself. Initially she doesn't appear to have much skill at witching magic, despite her large collection of magical jewellery, charms and such ordered from Ankh-Morpork.
In Witches Abroad, Magrat was chosen to serve as a Fairy Godmother, but her inability to master the use of the wand (which had a tendency to reset to "pumpkins") prevented her from taking full advantage of the powers associated with this position. She can defend herself physically when necessary, and is capable of performing impressive feats of real magic (as seen in Wyrd Sisters when she turns an old wooden door into a rising oak - a display that impressed even Granny Weatherwax).
Her forte however is as a herb-woman, doctor and pharmacist and she does better in these areas than the other witches (because she believes in it) whereas Granny tends to use whatever plant or bottle of coloured water comes to hand as a prop for her headology (the placebo effect). Being unusually literate for a Lancrastian, Magrat tends toward research, particularly into herbs and potions, following in the shoes of her mentor Goodie Whemper. She inherited Goodie's cottage and practice in the village of Mad Stoat, bringing a New Age attitude to an age-old society.
Magrat is a doer of good deeds and a worrier, a believer in the goodness of Nature and the psychic benefits of aromas and colours. Magrat believes in occult jewellery, magic knives, songs and folk wisdom. She is very much like a Roundworld New Age pagan, Pratchett poking fun of the whole concept. In fact she is the epitome of that wooly philosophy, nursing fallen baby birds until they die and never giving up hope until her husband and her country are attacked, at which point she channels Warrior-Queen Ynci and goes out in vintage armour like a Lancre Boadecia to save them.
Magrat meets her future husband, Verence, when he is the court jester or fool for the Duke of Lancre, Felmet (Verence is unaware of his heritage at that time.) They gradually and with great difficulty fall in love - neither very practiced or practical in the art of wooing. After a long engagement, Magrat marries King Verence II and becomes Queen of Lancre. Their engagement is not without strife as Magrat becomes completely fed up with Granny Weatherwax ordering her around and interfering in her life, especially when Granny convinces Verence to plan her entire wedding behind Magrat's back and without her consent. As a consequence of becoming queen, Magrat gives up on witching, abandoning all of her various magical trinkets by throwing them in the River Lancre. She helps repel the elves' invasion of Lancre by using old iron equipment and the non existent Warrior-Queen Ynci as inspiration.
In Carpe Jugulum, the couple has one daughter, Princess Esmerelda Margaret Note Spelling. This unusual name is due to Magrat's attempt to prevent a repetition of the mistake that her mother made. To ensure the child was named correctly, Magrat passed a note to the priest, Mightily Oats, appended with the words "Note Spelling". This backfired when he read out the complete sentence. Though he was mortified afterwards, the deed had been done and no attempt to change it could be made. Having a child and being a mother changes Magrat's personality - she's not wet behind the ears anymore, becomes more straightforward and decided. Later on she and Verence appear to have two more children, though these are not named.
As queen, Magrat tries to support Verence's ambition to modernise and democratise Lancre although she knows that the citizens have little appetite for change and less for democracy; she is a buffer between the eager king and his lackadaisical country.
After the events of Maskerade, Magrat retires from witching and is replaced by Agnes Nitt as the maiden. However, when Granny Weatherwax retires from witching, Magrat is forced to become a witch again, rejoining the coven in the role of the Mother, Agnes Nitt assuming her old role as the Maiden and Nanny Ogg becoming the Hag or old crone much to her chagrin. Despite Magrat's new (temporary) role at the end of the novel, she was asked to make tea by Granny Weatherwax, a role usually performed by the Maiden (in this case, Agnes Nitt). In The Shepherd's Crown, Magrat again takes on the "Mother" role in the battle to stop the Elves from spreading into the world. She leaves Verance at home to mind the kids, is instrumental in persuading Letitia, the Baron's wife, that being a witch is an important role, even for nobility, and that she should join the fray.
In the Wyrd Sisters animated adaptation, Magrat is voiced by Jane Horrocks.
A fossil species of Mesozoic ginkgo has been named Ginkgoites garlickianus after Magrat Garlick.