St. James suffered martyrdom A.D. 44 and, according to the tradition of the early Church, he had not yet left Jerusalem at this time (cf. Clement of Alexandria, Stromata VI; Apollonius, quoted by Eusebius, Church History VI.18).
In the year 1878, the Archbishop of Santiago – issued an instruction to find the relics of St. James and his two disciples, hidden three centuries earlier by order of Archbishop Juan Sanclemente. They had been hidden for fear of the English invasion of Admiral Drake.
The relics were rediscovered on 28 January 1879 in the floor of the cathedral retrochoir. When the Vatican was informed of their discovery, Pope Leo XIII declared the authenticity of the rediscovered sacred relics of Compostela in the Bull « Omnipotens Deus, » of 1 November, 1884.