At twenty, he left home, and the College of Charlemagne, where he had studied, imbued him with the doctrines of Voltaire.
Led at first by Philippe Buchez's neo-Catholicism and then won by the sermons of Lacordaire, he made his profession of faith to Gustave Delacroix de Ravignan (1837).
The Conferences of St. Vincent de Paul attracted the élite of the schools, and Olivaint with twelve of his companions established them in the parish of Saint Ménard.
After a year of professorship at Grenoble, he returned to Paris, and occupied the chair of history at Bourbon College; in 1841 he accepted a position as tutor to the young George de la Rochefoucaud.
After twenty-five years devoted to teaching, Olivaint was named Superior of the House in Paris (1865).
The next day, they took possession of the house on Rue de Sèvres, and Olivaint quietly gave himself up.
On 24 May, Darboy and five other prisoners were executed; on the twenty-sixth, fifty-two victims, with Olivaint marching at their head, were dragged through Paris and massacred in the Rue Haxo.
The cause for Olivaint and his companions was formally opened on 17 February 1937, granting them the title of Servants of God.