The Eucharistic miracle of Daroca was verified shortly before one of the numerous battles sustained by the Spanish against the Moors.
The Christian commanders asked the priest in the field to celebrate Mass, but a few minutes after the consecration, an improvised enemy attack obliged the priest to suspend the Mass and hide the consecrated Hosts amid the lines of the celebration.
The Spanish left the battle victorious and the commanders asked the priest to communicate the Hosts previously consecrated.
However, they were found completely covered in Blood. Even today, it is possible to venerate the blood-stained linens.
In 1239, the Christian cities of Daroca, Teruel and Calatayud (in Aragon) allied themselves to reconquer the walls of the castle of Chio.
Located at the castle of Chio during the first battle, during which having consecrated six Hosts designated for Communion for the captains that led the troops: Don Jimeno Pérez, Don Fernando Sánchez, Don Pedro, Don Raimundo, Don Guillermo and Don Simone Carroz.
An improvised attack of the enemy obliged the chaplain to immediately suspend the Mass, and coil the six consecrated Hosts in the corporal and to hide them under a rock.
The enemy troops had been forced back and the commanders begged the priest to be able to receive Communion in thanksgiving for the obtained victory.
Don Mateo brought them to the place where he had hidden the corporal and they found the Hosts drenched in Blood.
The commanders interpreted this event as a great sign of predilection on the part of God and of good auspices.
They received Communion and tied the blood-stained corporal to a spear to make a banner.
Like this, they brought the banner in battle against the walls and with this banner they reconquered the Castle of Chio obtaining a miraculous victory.
This triumph was attributed to the Eucharistic miracle.
The six commanders went to all the different regions of Spain and each of them began to maintain that the corporal must go into each city.
This began an open discussion.
Three times, the city of Daroca was chosen to be the custodial place of the miracle to the place where he had hidden the corporal and they found the Hosts drenched in Blood.
They arrived at a compromise.
They decided to place the corporal on the back of a mule to be left to wander freely; the city where the mule would stop would be the place chosen by the Divine Will to be custodian of the corporal.
The mule traveled for 12 days, walking about 200 miles, until, exhausted, it collapsed in front of the Church of Saints Mark in Daroca.
Following this, a church dedicated to Our Lady was constructed along with a precious reliquary where, even today, it is possible to venerate the blood-stained corporal.