On 7 September 1921, Frank Duff established the Legion of Mary in Dublin, Ireland as an association of catholic laity united in common devotion to the Blessed Virgin Mary.  It is the largest apostolic organization of Catholic laity in the world with more than three million active members worldwide.

Duff hoped that the Legion of Mary would help Catholics to life their baptismal promises in an organization united by fraternity and prayer.  Initially membership was reserved to women and men, other than Frank Duff himself, did not join the Legion until 1929. Life in Dublin had made him familiar with the struggles of the poor and saw a need for Catholics to offer and see material as well as spiritual nourishment.

Members are devoted to the Spiritual Works of Mercy through providing aid to all those in need both Catholic and non-Catholic.  Members are also encouraged to practice the Marian devotion exemplified by St. Louis de Monfort.

Prayer by Frank Duff

Oh, my God, I do not ask for the big things – the life of the missionary or the monk, or those others I see around me so full of accomplishment, I do not ask for any of these; but simply set my face to follow out unswervingly, untiringly, the common life which day to day stretches out before me, satisfied if in it I love You, and try to make you loved. Nature rebels against this life with its never-ending round of trivial tasks and full of the temptation to take relief in amusement or change. It seems so hard to be great in small things, to be heroic in the doing of the commonplace; but still this life is Your will for me. There must be a great destiny in it. And so, I am content. And then to crown the rest, dear Jesus, I beg you to give me this ,fidelity to the end, to be at my post when the final call comes, and to take my last, weary breath in Your embrace. A valiant life and faithful to the end. A short wish, dearest Jesus, but it covers all.
“Can we be Saints” by Frank Duff, age 27 years. Published 1916 with ecclesiastical approval

Website of the Legion of Mary