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Legion of Mary


The Legion of Mary is an international association of members of the Roman Catholic Church who serve it on a voluntary basis. It was founded in Dublin, as a Roman Catholic Marian Movement by the layman and civil servant Frank Duff.

Today, active and auxiliary (praying) members make up a total of over 10 million members worldwide, making it the largest apostolic organization of lay people in the Catholic Church.

Membership is highest in South KoreaPhilippinesBrazilArgentina and the Democratic Republic of Congo, which each have between 250,000 and 500,000 members. Membership is open to those who belong to the Catholic Church and believe in its teaching. Its stated mission is for active members to serve God under the banner of Mary by the corporal and spiritual works of Mercy, as mentioned in Chapter 33 of the Legion of Mary Handbook. The main apostolate of the Legion is activities directed towards Catholics and non-Catholics encouraging them in their faith or inviting them to become Catholic. This is usually done by encouraging them in prayer, attending Mass and learning more about the Catholic faith. The members of the Legion are engaged primarily in the performance of spiritual works of mercy, rather than works of material aid


The Legion of Mary was founded by Frank Duff on 7 September 1921 at Myra House, Francis Street, in Dublin. His idea was to help Catholic lay people fulfil their baptismal promises to be able to live their dedication to the Church in an organized structure, which would be supported by fraternity and prayer. The Legion draws its inspiration from 

Louis de Montfort's book True Devotion to Mary.

The Legion first started out by visiting women with cancer in hospitals, but it soon became active among the most destitute, notably among Dublin prostitutes. Duff subsequently laid down the system of the

Legion in the Handbook of the Legion of Mary in 1928.

The Legion soon spread around the world. At first, it was often met with mistrust because of its then-unusual dedication to lay apostolate. After Pope Pius XI praised it in 1931, the Legion had its mistrust quelled.

Most prominent for spreading the legion was Edel Quinn (1907-1944) for her activities in Africa in the 1930s and the 1940s. Her dedication to the mission of the legion, even in the face of her ill health (tuberculosis) brought her great admiration inside and outside the legion. A beatification process is currently under way for the legendary Quinn, as well as for Duff and Alfie Lambe (1932–1959), the endearing Legion Envoy to South America.

On 27 March 2014, the Secretary of the Pontifical Council for the Laity, Bishop Josef Clemens, delivered the decree in which the Legion is recognized by the Holy See as International Association of the Faithful.


The basic unit of the Legion is called a Praesidium, which is normally based in a parish. The Praesidium, usually a group of 3–20 members, meets weekly in its parish. The Curia is the next level, each supervising several Praesidia.

The next level is the Comitium, which is in charge of several Curiae, usually over an area like a medium city or a part of a province. The next level is the Regia, which is in charge of larger territories like a province or state (like in the US and Brazil). The Senatus is the next level, and it generally has control over the Regiae in a very large area, usually a country or a very large territory.

The Concilium is the highest level and has its seat in Dublin. It has control over the whole Legion.


Each level of the Legion has the same officers: the President, the Vice-President, the Secretary, the Treasurer, and the Spiritual Director. The last is always in the clergy, but all other offices are held by the laity. All positions regardless of responsibility are voluntary and the Legion has no paid workers.

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