Immaculate Conception (a doctrine of the Roman Catholic church which teaches that the Virgin Mary was in her conception exempt from all stain of original sin. Though this belief had been held in the eastern and western churches from a remote antiquity, it was not defined as an article of faith until Dec. 8, 1854. It is formally stated in the constitution of Pius IX., Ineffabilis Deus, in the following words: "We define the doctrine which holds the most blessed Virgin Mary in the first instant of her conception to have been preserved free from all stain of original sin, by the singular grace and privilege of Almighty God and through the merits of Jesus Christ the Saviour of the human race, to be a doctrine revealed by God, and therefore to be firmly and constantly held by all the faithful." The decree itself is further explained by the annexed passage from the constitution Sollicitudo omnium Ecclesiarum of Alexander VII.: " It is an ancient belief of Christ's faithful with regard to his virgin mother, that her soul in the first instant of its creation and union with the body was, by a special grace and privilege of God,. . . preserved free from the stain of original sin; and it is in this belief that they honor and celebrate the feast of her conception." The defined doctrine therefore refers not to the active but to the passive conception, that is, to the soul and body of the Virgin in the first instant of their creation and union; at that instant, in view of the merits of the Son, the mother, in body and soul, was exempt from the common law of fallen humanity.

The controversy within the Roman Catholic church on the immaculate conception was more in regard to the terms of the doctrine and the mode and time of the immaculateness than to the Virgin's freedom from the effects of original sin, which for the most part was not denied. The establishment of the feast of the conception witnesses to the fact; as the church could not celebrate a festival in honor of a conception in sin. This festival was celebrated at a very early day in the East, and it is almost impossible to fix the precise date of its introduction in the West; it was probably during the 8th and 9th centuries. In the East there seems to have been no discussion in regard to the observance of this festival. In the West it began to be observed by the devotion of particular churches before the sanction of the apostolic see had made it universal. St. Bernard reproved the canons of Lyons because they had established this feast without waiting for the decree of the supreme pontiff. The agitation of the question led to long disputes among theologians, and especially among the Franciscans and Dominicans; the latter have been ranked among the pronounced opponents of the doctrine. The disagreement was, however, one of terms rather than of doctrine.

Thus Thomas Aquinas, who is most eminent among the Dominican theologians, expressly declares the exemption of the Virgin Mary from original sin: "Talis fuit puritas B. Virginia, quae peccato originali et actuali immunis fuit" (Com. in I Liber. Sent., Dist. 44, § 3.) The objections of St. Bernard also are against the immaculate conception "actively" considered, which is no part of the Roman Catholic dogma. The discussion of the subject in the schools led to repeated declarations in its favor. Duns Scotus in 1307, in a disputation before the university of Paris, maintained the doctrine of the Virgin's immaculateness in its highest sense; and the whole Franciscan order thenceforward zealously defended it. The university itself in 1387 condemned certain propositions of John de Montesano, a Dominican, in which the doctrine was denied, and in 1497 passed a decree that no one should be admitted to any academic honor who did not bind himself by oath to defend it. In 1439 the council of Basel, during its schismatic period, declared the "belief of the immaculate conception of the Virgin to be conformable to the doctrine and devotion of the church, to the Catholic faith, right reason, and the Holy Scriptures, and to be held by all Catholics." The council of Trent, in its decree concerning original sin, expressly declared that it did not intend to include the immaculate Virgin, and ordered the decrees of Sixtus IV. to be observed.

During all the controversy the holy see interfered only occasionally, but these interferences were successive steps toward the formal definition of the doctrine. Sixtus IV., in the apostolic letter entitled Grave nimis, published in 1480, imposes excommunication upon any one who accuses of heresy either the advocates or the opponents of the immaculate conception, while at the same time he condemns all who affirm as the truth the opinion that the Blessed Virgin was conceived in sin. He also granted indulgence to those who should assist at mass or office on the feast of her conception. Pius V., in the bull 114, Super Speculam, in 1570, prohibited the public discussion of the question, renewing also the decree of his predecessor. Paul V. in 1616 forbade any one to affirm by any public act whatever that the Virgin was conceived in sin, while he also prohibited the open condemnation of this opinion. Gregory XV. in 1622 prohibited either the public or private denial of the immaculate conception, allowing no discussion whatever on the subject except to the Dominicans, to whom an especial privilege was reserved.

The office and mass of the conception were however made binding upon them as upon all Catholics. In 1661 Alexander VII., in the constitution Sollicitudo omnium Ecclesiarum, declares the opinion that the Virgin was conceived without original sin to be almost universal in the church; therefore he renews the decrees of his predecessors, commanding that they be observed in favor of the feast and cultus of the conception, and moreover deprives of the faculty of teaching or preaching any one who should call into doubt or misinterpret the favor shown to this opinion by asserting anything against it, or even by bringing forward arguments against it. After that time the congregation of rites repeatedly interposed its mandate in favor of the doctrine. The word immaculate was added in the office and mass of the conception, and its use made binding upon all priests, even those of the Dominican order. Pius IX. in the early part of his reign sent letters to all patriarchs and bishops, requesting their opinion upon the propriety of defining the doctrine. Answers were given by 620 bishops and archbishops, of whom only four were opposed to the definition on dogmatic grounds, and even these gave testimony that their clergy and people were united in the belief of the doctrine.

When replies were received from nearly the whole Catholic episcopate, as many of the bishops as possible were invited to be present in Rome to assist at the solemn definition of the doctrine. This ceremony took place with great pomp in the basilica of St. Peter, in the presence of more than 300 archbishops, bishops, and prelates, on the feast of the immaculate conception, Dec. 8, 1854. In September, 1857, a monument was inaugurated by the pope at Rome in commemoration of the decree. On this occasion he also established the " Archconfrater-nity of the Immaculate Conception," which now has branches in all Catholic countries. - In 1618 a military order of the Conception was established in Italy by Duke Ferdinand I. of Mantua, for promoting peace among Christian princes; this order was confirmed in 1625 by Urban VIII., who gave to the members the rule of the third order of St. Francis. It was composed of noblemen, and rapidly acquired great importance; but political events caused its dissolution. In Portugal John VI. founded, Feb. 6, 1818, the military order of "Our Lady of the Conception of Villaviciosa."