Starting before the First Crusade, many hospices and hospitals were organized by the chapters of cathedrals or by the monastic orders. Within the communal organizations of towns, local charitable institutions such as almshouses were established by confraternities or guilds, or by successful individual laymen concerned with the welfare of their souls, but often only local historians are aware of them.
Broader-based and aristocratically-funded charitable institutions were more prominent and are more familiar, and the episodes of aristocratic and even royal ransom and its conditions, were the subject of chronicle and Romance. The knights of the original Order of St John— the Knights Hospitaller— and the Templars in their origins are well known, and the impact of their organized charity upon the religious values of the High Middle Ages is more fully estimated in their spheres.
The Order of Merced, however, an early 13th-century popular movement of personal piety organized at first by the Catalan Peter Nolasco, was concerned with ransoming the ordinary men who had not the means to negotiate their own ransom, the "poor of Christ" Nolasco and the fraternity that grew around him were motivated by an urban mentality that transcended kith and kin in a broader social consciousness; though they were lay folk, such a movement could only find expression through a specifically Christian form: within its first five or six years the movement was organized into a recognized order of the Church, still in the early 13th century the one transcendent institutional framework in Europe aside from the Papacy. (Brodman 1986).
St. Peter Nolasco began his redemptive work (ransoming Christian captives) in 1203.
After fifteen years of admirable mercy in the redemption of Christian captives, Peter Nolasco and his friends were seeing with concern that, instead of decreasing, day by day the number of captives was growing excessively. The determined leader, with a strong personality, clear ideas, a strong faith, a solid and balanced devotion to Christ and to his Blessed Mother, a compassionate heart, a serene and resolute trust in God, Peter Nolasco did not feel overwhelmed by the magnitude of the mission undertaken and his own insignificance. In his fervent prayer, he sought divine inspiration to be able to continue God’s work which he had started. At that point and in these circumstances, during the night of August 1, 1218, a special intervention of Blessed Mary occurred in Peter Nolasco’s life: an amazing Marian experience which illumined his mind and stirred up his will to transform his group of lay redeemers into a Redemptive Religious Order which, with the Church’s approbation and the protection of the Count of Barcelona and King of Aragon , would pursue the great work of mercy which had started.
On the next day, Peter Nolasco went to the royal palace to explain his project to young Count of Barcelona and King of Aragon, James I and his advisers, the first of whom was the Bishop of Barcelona, don Berenguer de Palou. Peter’s plan, inspired by God through Mary, was to establish a well-structured and stable Redemptive Religious Order under the patronage of Blessed Mary. The proposal pleased the king and his advisers since, after the failed attempt by Alfonso II with the Order of the Holy Redeemer which did not prosper, the noble aspiration of the royal house of Aragon to have its own redemptive order was becoming a reality.
On August 10, 1218, the new religious order for the Redemption of Captives was officially and solemnly constituted at the main altar erected over Saint Eulalia's tomb in the Cathedral of the Holy Cross (also known as the Cathedral of Santa Eulalia) in Barcelona. Bishop Berenguer de Palou gave Peter Nolasco and his companions the white habit that they would wear as characteristic of the Order; he gave them the Rule of Saint Augustine as a norm for their life in common and he gave his authorization for the sign of his cathedral, the Holy Cross, to be on the habit of the Order. After that, Peter Nolasco and the first Mercedarians made their religious profession right there before the bishop.
For his part, King James I the Conqueror established the Order as an institution recognized by the civil law of his kingdom. In the very act of the foundation and as an important rite of the ceremony, the monarch gave the Mercedarian friars the habit which, in the language of military orders, is the shield with four red stripes over a gold background, that is to say, the sign of the king himself. Along with the cross of the cathedral, this emblem would form the Order’s own shield. On that memorable day, James I endowed the Order, of which he considered himself the founder, with the Hospital of Saint Eulalia which served as the first Mercedarian convent and as a house of welcome for redeemed captives.
In the proem of the first Constitutions of the Mercedarian Order of 1272, three very important elements referring to the foundation stand out: the name, the founder and the purpose of the Order.
The name with which the Order founded by Peter Nolasco is identified, is mentioned first. Prior to the 1272 Constitutions, the Order had several names among which: Order of Saint Eulalia, Order of the Mercy of Captives, Order of the Redemption of Captives, Order of Mercy. But the proper and definitive title is: Order of the Virgin Mary of Mercy of the Redemption of Captives.
Then it is stated that Brother Peter Nolasco has been constituted "servant, messenger, founder and promoter" of the new Institute. Peter Nolasco is the real founder of the Order or the "Procurator of the alms of captives" as defined on March 28, 1219, by the first document referring to him after the foundation.
Finally, it is clearly specified that the purpose of the Order is "to visit and to free Christians who are in captivity and in power of the Saracens or of other enemies of our Law… By this work of mercy… all the brothers of this Order, as sons of true obedience, must always be gladly disposed to give up their lives, if it is necessary, as Jesus Christ gave up his for us."
All these valuable and reliable historical details of the foundation of the Order of Mercy are gathered in the letter of January 11, 1358, sent by Peter IV of Aragon the Ceremonious to Pope Innocent VI and kept to this day in the Archives of the Aragon Crown, a reliable guarantee of all the Mercedarian history of the first centuries.
With the solemn and official support of the Church and of the state, Peter Nolasco and his friars, constituted as a Redemptive Religious Order of lay brothers, gained new energy and, with renewed fervor, they continued their peregrinations of charity to collect alms for the redemption of captives in Saracen lands.
These additional vows are part of the nature of the profession of each Order and are permitted by the Church. They can be solemn or simple, perpetual or temporary. The Fourth Vow of the Order of Mercy is a Solemn Vow. In accordance with the general principle of a vow, it is an act of the will and an authentic promise in which the reason for the vow is perfection. It also presupposes a sincere will of obligation in conscience and by virtue of the community.