Of all the communities and religious orders in the Roman Catholic church that are involved in missionary activity, the Congregation of the Mission, while one of the more extensive, is undoubtedly the least known. Founded in 1625 by Saint Vincent de Paul (1581-1660), its original purpose was the giving of parish missions in the de-Christianized rural areas of France. The rural missions remained a special concern of Saint Vincent's community and it was in this sense that the term “mission” was originally used. Prior to the French Revolution the term missionary was used almost exclusively of members of Saint Vincent's group. In the mid-eighteenth century they also came to be known as Lazarists, a name derived from their motherhouse, the famous Saint-Lazare. Though this name has been used in other countries, the Congregation of the Mission has come to be known by different names in different localities: for instance, Vincentians in the English-speaking world, Padres Paúles in the Spanish-speaking world, and Saint Vincent's Fathers in Nigeria.
Reacting against the excessive esprit de corps of numerous religious groups of his time, Vincent de Paul decreed that the work of his missionaries should be without fanfare or publicity. He even forbade some of them from writing histories of the community lest this should lead to corporate pride. It was an unfortunate precedent. This tendency, plus a general lack of historical consciousness, has caused the work of the Congregation of the Mission to be unpublicized and unknown, even by the members themselves.