MISSIONARY UNION OF THE CLERGY. - The distant origins of the Missionary Union of the Clergy (U.M.d.C.) are intertwined with the history of the apostolate, which priests have always exercised for the conversion of peoples, but its strict precursors date back to the late 19th century.
In the Netherlands, the clergy had been involved through the Apostolic League. In Germany, Fr. Giuseppe Schmidlin (q.v.) gave rise to various priestly associations for the missionary cultural formation of the clergy. However, the credit for having established an organization of priests committed to effective missionary cooperation belongs to Fr. Paolo Manna of the Pontifical Institute for Foreign Missions (q.v.), born in Avellino on 16 January 1872 and died in Naples on 15 September 1952. As early as 1908, Manna had proposed the idea in his book *Operarii autem pauci*, and by the end of 1915 he had drafted the first outline of the statutes for the Union, which, through the mediation of Msgr. Guido M. Conforti (q.v.), was presented to Benedict XV on 27 April 1916. The Sacred Congregation for the Propagation of the Faith approved it on 31 October of the same year. The U.M.d.C. was immediately established in Italy and soon enriched with privileges and indulgences. The apostolic letter *Maximum illud* (1919) officially consecrated its existence, extending it to the entire world. The success of the U.M.d.C. was now assured, and today it is established in all countries and even in missionary territories.
The statutes of 1916 were temporarily approved in 1921. In 1926, the definitive statutes were issued, later modified in 1937 following the establishment of the International Secretariat, decreed in 1936. The International Secretariat, headed by the General Secretary, is the center of all national Directions of the U.M.d.C., from which the respective diocesan Directions depend. Secular and religious priests, as well as theology students, may join the U.M.d.C., and upon assuming its obligations, they enjoy numerous spiritual favors also granted to all missionaries. With a decree of 14 July 1949, the Sacred Congregation for the Propagation of the Faith again approved the statutes regarding the action of the U.M.d.C. for lay religious and sisters, who may join through personal or collective registration, enjoying special spiritual privileges.
Among the various initiatives, the "Day of the Sick" is noteworthy: on Pentecost, they offer their sufferings for the missions.