Tradition has it that Saint James the Apostle of Jesus (in Spanish, Santiago Apostol) went from Israel to Spain preaching Christianity. He was, therefore, if the tradition is correct, the first Apostle to evangelize the Iberian Peninsula. Saint Paul talked about going to Spain, but more than likely never did.
Many scholars doubt this tradition because Saint James died rather early, and in Jerusalem, not in Spain, in the year 44AD. On the other hand, this would have given him roughly ten years to make the trip to Spain, from the time of Jesus' Ascension and the time of his own death in 44AD.
The tradition continues that the body of the martyred saint was brought back to Spain and buried in Galicia. In time, his tomb was forgotten due to wars and foreign invasions. Then, centuries later, a shepherd, guided by a star, was lead to the burial site and discovered it. From then on, a succession of churches were built on the site, called Compostela because, as tradition has it, it was a star (stella) that lead to the discovery of the field (campus) where the body lay. Again, some scholars dispute this and think the name comes from other possible origins.
Whatever the case, the cathedral/shrine to Saint James in Compostela became a major destination for Christian pilgrimages in Europe. It was the shrine of an Apostle, a big deal to Christians. Yet, it was safely in Christian lands, not like the other holy places in the East which were under Muslim control and more dangerous for Christians to travel.
The Cathedral of Santiago de Compostela
In the Middle Ages, the shrine of Saint James in Spain was a major pilgrimage center for all of Western Europe. A series of roads eventually were mapped out to bring pilgrims - walking by foot - to the shrine. It was called the Camino de Santiago, the Way of Saint James. All along the route, there were specially-marked towns where pilgrims could receive hospitality. There, a church official would mark a certificate with a stamp that the pilgrim had reached that far. When they completed the journey to Compostela, they received the final recognition they had fulfilled the pilgrimage and gained the graces and indulgences attached to it.
Saint James dressed as a Pilgrim
concha de vieira in the Galician language, became associated with the pilgrimage to Santiago and we're not sure why. We do know that one wore these shells after one completed the pilgrimage, on the way back home. Nowadays, people wear them on the way to Santiago.
Modern Pilgrim in Traditional Attire
The medieval pilgrim, who went on foot, carried a staff. He wore a wide-brimmed hat for protection. He wore a cape and carried a water gourd and a pouch or wallet.
San Roque dressed as a Pilgrim
Gourd, staff, wide-brimmed hat and shell.
The Pilgrim's Passport, marked with the stamps of some of the official towns and churches along the Camino de Santiago, the Way of Saint James.
When one reaches the shrine at Santiago, one receives the Compostela, the certificate of completion.
In addition to all this, Saint James rose in prominence in Spain when the Spaniards warred against the Muslim Moors who had ruled over their country for many years. A Spanish king dreamt of Saint James, who then lead them in battle, appearing on horse back. The Christians defeated the Muslims, and Saint James was then known as Matamoros - the Moor killer!
Patron of Paete, Laguna Province in the Philippines