Jansenism was a theological movement within Catholicism, primarily active in France, that emphasized original sin, human depravity, the necessity of divine grace and predestination. It was declared a heresy in the Catholic Church. The movement originated from the posthumously published work of the Dutch theologian Cornelius Jansen, who died in 1638. It was first popularized by Jansen's friend Abbot Jean du Vergier de Hauranne, of Saint-Cyran-en-Brenne Abbey, and, after du Vergier's death in 1643, was led by Antoine Arnauld. Through the 17th and into the 18th centuries, Jansenism was a distinct movement away from the Catholic Church. The theological center of the movement was the convent of Port-Royal-des-Champs Abbey, which was a haven for writers including du Vergier, Arnauld, Pierre Nicole, Blaise Pascal and Jean Racine.
Jansenism was opposed by many in the Catholic hierarchy, especially the Jesuits. Although the Jansenists identified themselves only as rigorous followers of Augustine of Hippo's teachings, Jesuits coined the term Jansenism to identify them as having Calvinist affinities. The apostolic constitution Cum occasione, promulgated by Pope Innocent X in 1653, condemned five cardinal doctrines of Jansenism as heresy—especially the relationship between human free will and efficacious grace, wherein the teachings of Augustine, as presented by the Jansenists, contradicted the teachings of the Jesuit School. Jansenist leaders endeavored to accommodate the pope's pronouncements while retaining their uniqueness, and enjoyed a measure of peace in the late 17th century under Pope Clement IX. However, the further controversy led to the apostolic constitution Unigenitus, promulgated by Pope Clement XI in 1713.