From the beginning of his priestly ministry in December 1700, Louis-Marie envisioned a Congregation ready to go anywhere to teach catechism to the peasants, the poor, and the children. During his 15 years of missionary life, Montfort had priest collaborators like Mr. des Bastières or Gabriel Ollivier who accompanied him for several years, but were not so steady. Around 1712, in La Rochelle, he wrote a Rule for the Missionary Priests of the Company of Mary, a rule where teaching of catechism to the children has an important place.

It was not until February 1715 that this Company had the first priest: Adrien Vatel (1680-1748), a young Norman priest, a former student of the Seminary of the Holy Spirit of Claude Poullart des Places, but he did not commit himself with vows until 1722. In September 1715, a young priest of the diocese of La Rochelle, René Mulot (1683-1749), despite his poor health, agreed to join Father de Montfort. He became the first Superior General of the Company of Mary in 1722.

In December 1701, Montfort met in a church at Poitiers, a young 17-year-old girl, Marie–Louise Trichet (1684-1759), who came to confession to him. Montfort had the intuition that God could do great things through her. He asked her in January 1703, to come and work at the General Hospital of Poitiers, as a servant of the poorest, and to join the Association of Wisdom led by a blind woman.

On February 2, 1703, the daughter of the bourgeoisie received from Montfort a humble peasant’s gray coat and the name of Marie–Louise of Jesus. For 12 years, as a novice, she devoted herself in this general hospital which collected all those disinherited of life. In 1713, a companion joined her: Catherine Brunet. In 1715, Montfort asked Marie-Louise and Catherine to leave Poitiers for La Rochelle, to run a charitable school and to take care of the Saint-Louis Hospital. On August 1, 1715, Bishop Champflour approved the Rule of the Daughters of Wisdom written by Louis-Marie and reviewed by Marie-Louise. On August 22, 1715, Marie–Louise Trichet, Catherine Brunet, Marie Valleau and Mary Regnier made their first profession. Marie-Louise was appointed superior.

In 1705, in a church of Poitiers, Louis Marie asked a young man of 18, Mathurin Rangeard (1687-1760), to follow him. Mathurin became his constant companion in the missions and he continued this ministry until his death in 1760. Other brothers such as John, Peter, Nicolas, Jacques, Philippe, Gabriel, Louis, also joined Montfort to help him.

At the Pentecost 1715, according to tradition, four of them, Louis, Philippe, Gabriel and Nicolas, pronounced their vows of obedience and poverty forming the nucleus of the Brothers of the Holy Spirit. Mathurin and Jacques, did not dare take that step, even though they were devout followers of Montfort. In 1715, Montfort, concerned with the pastoral plan of Mgr. Champflour, Bishop of La Rochelle, asked some brothers to work in the “charitable school” at La Rochelle (1715) and at Nantes. In his testament of 27 April 1716, Montfort gave a considerable place to the brothers and envisaged that some of them work in the charitable schools.