France in the late 17th century was suffering from the effects of the Franco-Spanish War (1635–1659) and a terrible plague. As a result of his efforts to promote a planned parish mission in the nearby village of Sotteville-lès-Rouen, Barré came to see the suffering of the local population. To enable parents to attend the mission, Barré asked two young women to come and help with the children. One was a local resident, Françoise Duval, 18 years old, the other was Marguerite Lestocq, then aged 20, who, like him, was from Amiens and with whom he had family connections.