He was born on 25 October 1808 at 8 p.m. in Roquemaure (Gard). He was the son of Mathieu Cappeau, a cooper, and Agathe Louise Martinet. From the beginning, he was destined to follow his father in the family business (vinification and cooperage); but after an accident, he turned to the life of an academic. The accident occurred when he was eight years old, while "playing" with his friend Brignon. The young Brignon was handling a gun and shot Cappeau in the hand. This led to the young Cappeau having to undergo an amputation of his hand. Thanks to the financial support from Mr Brignon who supplied half of tuition, Placide Cappeau was able to attend a town school and was accepted into the Collège Royal d’Avignon. While there, in spite of his disability, he was awarded the first prize in drawing in 1825.
After studying in Nîmes, where he received a baccalauréat littéraire (A level in literature), he studied law in Paris and was awarded a license to practice law in 1831.
Following in his father's footsteps, to an extent, he became a merchant of wines and spirits. However, his focus in life was literature.
According to Placide, he wrote the poem "Minuit Chrétien" (O Holy Night) in a stagecoach to Paris, between Mâcon and Dijon. More likely, this famous Christmas carol was written by Cappeau in the usual way. Adolphe Adam called his tune "la Marseillaise religieuse" (The religious Marseillaise), reflecting the republican and anti-clerical (secular), and even somewhat socialist views of Cappeau, which reflect the spirit of the original poem.
Other writings include Le château de Roquemaure, which was published in 1876, Le roi de la fève, La poésie, Le papillon and La rose.
He died on 8 August 1877 in Roquemaure, at the age of 69.
- Durieu (abbé René), L'auteur du "Minuit chrétiens", Placide Cappeau, Nîmes, Lacour, 1996.