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"Rionach never married or had children, as rumour had it that she had the ability to speak Parseltongue like her ancestor Salazar Slytherin, and did not want his powers to be passed down any further."
— Rionach's rumour to be a Parselmouth[src]

Rionach Steward (b. 1600s) was an American half-blood[2] witch and the younger twin daughter of Isolt Sayre and James Steward. Isolt and James were the founders of Ilvermorny School of Witchcraft and Wizardry. Rionach would later become one of the school's first Defence Against the Dark Arts instructors, teaching there for many years.[1]

Rionach chose not to marry and remained single. There was a rumour she was born with the ability to speak Parseltongue, and because of this was determined not to pass on Slytherin ancestry into the next generation, thus her decision to never marry.[1]


Rionach Steward was born in or around 1634 at Ilvermorny in Massachusetts, along with her older fraternal twin sister, Martha. Her parents, Isolt Sayre, a pure-blood witch, and James Steward, a No-Maj, were the founders of the school. She also had two older brothers by adoption: Chadwick and Webster Boot. She was named after her late maternal grandmother.[1]

Rionach was born with magical abilities, whereas her elder twin was born a Squib.[1] It was also rumoured — though it was never confirmed by the family — that she was born a Parselmouth, a frequent trait in her maternal family, descendants of Salazar Slytherin (sometimes known to his contemporaries as "Serpent-tongue").[3][1]

When she was a baby, her great-aunt, Gormlaith Gaunt, attacked the family due to her prejudice against Muggles. Her parents had been put in a deep sleep by Gormlaith, but the cries of baby Rionach and her sister Martha woke them, since the curse took no account of the power of love. The family were saved by William, the Pukwudgie her mother had befriended several years earlier.[1]

Rionach went on to become the teacher of Defence Against the Dark Arts at Ilvermorny. She never married or had children, determined not to let the Slytherin and Gaunt bloodlines to continue (which was ultimately fruitless, since the American branch of the family was unaware that Gormlaith was not the last of the Gaunts in England).[1]

Magical abilities and skills

  • Defence Against the Dark Arts: Rionach was very talented in defensive magic, as she went on to become a professor of Defence Against the Dark Arts at Ilvermorny School of Witchcraft and Wizardry, showing her talent and knowledge in this field.[1]
  • Parseltongue (possibly): Rionach was rumoured by some, but never proven, to have possessed the rare ability of Parseltongue, the ability to speak to snakes. Some alleged her supposedly being a Parselmouth led her to not have any children in her lifetime, but whether or not she actually was a Parselmouth in reality, is unknown.[1]


  • Rionach is a variant of the name Ríoghnach, derived from Irish ríoghan meaning "queen". In Irish legend this was a wife of the Irish king Niall.
  • The surname steward comes from Middle English steward, from Old English stīweardstīġweard ‎meaning “steward, housekeeper, one who has the superintendence of household affairs, guardian”, from stīġ in the sense househall + weard  ‎“ward, guard, guardian, keeper”.

Behind the scenes

  • Although Rionach decided not to marry, her sister did, so there may still be descendants of Salazar Slytherin via Martha. It is possible that Rionach did not want to impose her choice on her sister as well, or that she tried but failed.
    • However Martha was a squib, and she married a man without magical powers. The fact that magic can resurface in the squib's descendants is a recent discovery, so it's possible that Rionach hasn't made any opposition to her sister's marriage.


Notes and references

Ilvermorny School of Witchcraft and Wizardry
Ilvermorny Houses
Horned Serpent ClearBG 2.png
Wampus ClearBG 2.png
Thundebird ClearBG 2.png
Pukwudgie ClearBG 2.png
Namesake Founders
Isolt Sayre · Chadwick Boot · Webster Boot · James Steward
Subjects offered
Arithmancy · Charms · Creature Care · Defence Against the Dark Arts · Potions · Study of Ancient Runes · Transfiguration · Xylomancy
Ilvermorny staff
William · Rionach Steward · Eulalie Hicks · Agilbert Fontaine