Which medieval knight wrote the memoir known as The Life of Saint Louis?

Jean de Joinville wrote The Life of Saint Louis, a memoir of King Louis IX of France. Joinville was a nobleman and crusader who served as seneschal of Champagne.

Written in the early fourteenth century, the work describes Louis IX’s character, government, religious devotion, and participation in the Seventh Crusade. Joinville had accompanied Louis on that expedition and drew on personal experience, conversations, and memories of the king.

The book is valuable because it combines biography, eyewitness testimony, moral reflection, and courtly storytelling. It does not provide a neutral modern biography: Joinville admired Louis deeply and presented him as an exemplary Christian ruler. Louis was canonized in 1297, several decades before Joinville completed the memoir, which helped shape the work’s devotional tone.