Why did the floor of a Spanish monastery turn blood red once a year for almost 500 years?

trappists The community of Trappist monks of the monastery of San Pedro de Cardeña in Burgos, Spain. | Photo credit: Archdiocese of Burgos

On Aug. 6 in the year 953, 200 monks living at the monastery of San Pedro de Cardeña in Burgos, Spain, were put to death, martyred by Muslim troops. From that time until the end of the 15th century, the flooring at their place of martyrdom turned red with blood once a year.

The prodigious event was repeated until a few years before the Reconquista (Reconquest) in 1492 with the final surrender of the Muslims holding out in Granada and the consolidation of Spanish territory under King Ferdinand and Queen Isabella, known as the Catholic Monarchs. 

According to some experts, the history of the monastery dates back to the fifth century, although the current residents of the convent today state that there is no historical evidence of it until the end of the ninth century.

In any case, San Pedro de Cardeña was an important Christian center for centuries and relics of St. Peter, St. Paul, and St. John the Evangelist — among others — were venerated there.

Like the entire area of Burgos, for decades the surroundings of the monastery were contested borderlands, where the struggles between the Christian and Muslim kingdoms took place. To mount their attacks, the Saracens also took advantage of the fighting between monarchs and Christian feudal lords.

The first Umayyad caliph of Córdoba, Abderramán III, took advantage of the disagreements between Ordoño III, the king of León, and Fernán González, the count of Castile, and launched the incursion that led to the martyrdom of the 200 Benedictine monks of San Pedro de Cardeña.

The looting of the monastery and killing of the monks out of hatred for the faith was recorded in the General Chronicle of Alfonso X the Wise, the first large-format history of Spain written directly in Castilian Spanish at the end of the 13th century.

García Fernández, the son of Fernán González, restored the monastery after it was looted. It was in the cloister where the monks were beheaded, known since then as the cloister of the martyrs, where the blood of the martyrs flowed every year until the reign of Henry IV, who died at the end of the 15th century.

His sister, Queen Isabella of Castile, was one of the most renowned pilgrims who came to San Pedro de Cardeña to honor the memory of the martyrs, as did the monarchs Felipe II, Felipe III, and Carlos II.

Popular devotion was such that in 1603, Pope Clement VIII authorized the cult through a pontifical brief, dated 1603.

El Cid and the monastery

The connection between the monastery of San Pedro de Cardeña and one of the most prominent figures of the Spanish Reconquista also gives the place a special aura.

According to the Cantar de Mio Cid, (The Song of My Lord), an epic poem about the famed warrior Rodrigo Díaz de Vivar (El Cid), it was the San Pedro de Cardeña monastery where El Cid left his wife Doña Jimena and his daughters when he had to go into exile in the second half of the 11th century. The abbot at the time was St. Sisebuto.

El Cid died in Valencia in 1099. His wife remained in command of the city, but the onslaught of the Muslims made it necessary for her to flee in 1102. She therefore decided to have the corpse of the mythical warrior moved from the Valencia cathedral to San Pedro de Cardeña.

El Cid’s tomb was desecrated in 1808 by Napoleon’s troops, but General Thiébault decided to place the remains of the knight in a mausoleum located on a main avenue in the city of Burgos. The remains were brought back to the monastery in 1826.

After the Spanish confiscation, in which the government nationalized the properties of the religious orders, including the convents, the remains of El Cid were transferred to the Burgos Town Hall chapel in 1842.

It was not until 1921 that the remains of El Cid  were laid to rest next to his wife in the Burgos cathedral.

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At the monastery, however, there is a monolith memorializing Babieca, the faithful horse of El Cid, where tradition says the animal was buried.

Attempts to restore monastic life

Due to the confiscation, the monastery of San Pedro de Cardeña was deprived of monks for 106 years. The Benedictine Order tried to restore monastic life there at the end of the 19th century without success, as they were unable to get the use of land to support the community.

Briefly, the Piarist Fathers occupied the monastery between 1888 and 1901. Four years later, some French Capuchin friars expelled from Toulouse arrived and remained there until 1921.

In 1933, a Cistercian community arrived at the place from San Isidro de Dueñas, in Palencia. The outbreak of the Spanish Civil War prevented their definitive settlement there until 1942, since the site was converted into a prison camp during the conflict. In 1948, the abbey obtained the title to the property.

At present, a community of Trappist monks lives in the monastery, and each August they commemorate the martyrdom of their predecessors.

This story was first published by ACI Prensa, CNA’s Spanish-language news partner. It has been translated and adapted by CNA.

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