Eruditio regum et principum (Education of Kings and Princes)
Eruditio regum et principum
Catalogue updated 2026-06-08
Full Sub Rosa translationRead the full translationOpen reader →Open the chapter reader with the full English translation, source text, notes, and scripture echoes.What is Eruditio regum et principum (Education of Kings and Princes)?
Written by the Franciscan theologian Guibert of Tournai expressly for Louis IX in 1259, while Guibert held the Franciscan chair of theology in Paris, this mirror for princes extends beyond political counsel to offer the king sustained guidance on virtue, self-discipline, justice, equity, and peace drawn from Scripture and the Fathers.
A verified public-domain excerpt for this text is still being set. The folio is catalogued and linked below; an original Sub Rosa rendering will follow.
What it is
Written by the Franciscan theologian Guibert of Tournai expressly for Louis IX in 1259, while Guibert held the Franciscan chair of theology in Paris, this mirror for princes extends beyond political counsel to offer the king sustained guidance on virtue, self-discipline, justice, equity, and peace drawn from Scripture and the Fathers. It is one of the most theologically serious of the royal mirrors produced for the Capetian court, reflecting the deep Franciscan intellectual influence on Louis's mature piety. A complete 14th-century manuscript survives in the National Library of Scotland, and Alphonse de Poorter produced a critical edition. Whether Guibert accompanied Louis on the First Crusade (1248–1254) remains uncertain.
Why it still matters
The treatise's sustained integration of virtue ethics with scriptural spirituality offers a practical guide to Christian leadership and self-governance that any person in public life can read profitably as a formation text.
Eruditio regum et principum (Education of Kings and Princes) companion
Louis IX kept a daily rule of reading. Keep yours.
After day 21, Chosen Portion keeps the habit going with one historic devotional portion each morning, free on iOS.
Guibert formed Louis IX through short scheduled installments, and Chosen Portion delivers formation in the same daily-installment pattern.
- One reading and prayer per day, about 3 minutes
- Continue with 78 royal and monastic works after the plan ends
- Reflection questions suited to reading with a teen or small group
Kept alongside
The Enseignements of Louis IX to his son Philip
Les Enseignements de saint Louis à son fils Philippe
Written in Louis IX's own hand for his eldest son and heir Philip (the future Philip III) around 1267–1268, three years before Louis died on crusade, these instructions address prayer, daily confession, devotion, justice, and the conduct of Christian kingship in a tone of direct paternal love. The text opens: 'To his dear eldest son Philip, greetings and paternal affection.' Although Joinville later incorporated a version into his Vie de saint Louis, scholars have established that Joinville substantially altered Louis's actual words; the primitive text was recovered and published by Henri-François Delaborde in the Bibliothèque de l'École des Chartes in 1912. As a first-person document of royal spirituality composed near the end of Louis's life, it has no peer in the Capetian corpus.
The Enseignements of Louis IX to his daughter Isabelle
Les Enseignements de saint Louis à sa fille Isabelle, reine de Navarre
A companion piece to the Enseignements for Philip, this shorter text was written by Louis IX for his daughter Isabelle, queen of Navarre (1241–1271), and is phrased throughout in the direct imperative: love God, pray daily, confess your sins, conduct yourself uprightly. Louis explains in the opening lines that he believed his instructions would be retained more willingly precisely because they came from him through love rather than from a schoolmaster. The text survives in multiple manuscripts and was edited from the records of the Société de l'Histoire de France. Together with the Enseignements for Philip, it shows Louis applying the same Franciscan-inflected spirituality to both his son's governance and his daughter's personal sanctification.
De eruditione filiorum nobilium (On the Education of Noble Children)
De eruditione filiorum nobilium
Commissioned by Queen Marguerite of Provence from the Dominican encyclopedist Vincent of Beauvais — who served as lector in theology at Royaumont Abbey near the royal court and enjoyed direct Capetian patronage — this was the first systematic pedagogical manual for noble children in the Latin West and the first to address the educational needs of noble women directly. Written to guide the tutors of Louis IX's own children, it grounds its pedagogy in virtue formation, habitual prayer, and scriptural study drawn from Augustine, Jerome, and Chrysostom. The work circulated beyond the court and influenced later medieval educational writing; Vincent conceived it as part of a larger projected work on the governance of the French realm. It survives in multiple manuscripts and has been critically edited from the University of Missouri manuscript tradition.