Mechtilde of the Blessed Sacrament, born Catherine de Bar (31 December 1614 – 6 April 1698) was a French nun, the founder of the order of Benedictine Nuns of Perpetual Adoration of the Blessed Sacrament.

In May 1635, Mother de Bar, and the nuns of the convent in Bruyères were forced to flee before the Swedish army.

Catherine de Bar and five other nuns found shelter with the Benedictines in Rambervillers.

[2] In 1653 in Paris[1] she founded the Order of the Benedictine Nuns of Perpetual Adoration of the Blessed Sacrament.

[3] This was the first society formally organized for the Perpetual Adoration of the Blessed Sacrament[4][5] Mectildiana - collected works of Mechtilde in 13 volumes.