From the Spirit of Charity blog, reflection by Sr. Marjory Ann Baez, D.C.:

During the French Revolution in the late 1700s, a number of Daughters of Charity were among the hundreds of faithful priests, religious, and ordinary Catholics who were killed because they would not take the oath required by the revolutionary government of France. This oath separated those who took it from the Catholic Church in Rome. June 26 is the feast day of these five Daughters of Charity who were guillotined by the revolutionary government […] four Daughters of Charity from Arras who were martyred in 1794. One other sister, Sister Marguerite Rutan, was guillotined in the city of Dax.

Resources

Two slide presentations are available below.