S Martinus Ep Sagunt was an enigmatic personage born in some undetermined date of the XII century from the disappeared Royal Monastery of San Benito de Sahagún ? He reached the bishopric of one of the numerous small dioceses that at that time surrounded the city of Augsbourg. There is evidence that in 1213 he attended the consecration of the monastery of Santa Maria de Óvila together with San Martin de Hinosoja, and died around 1218.
The Monastery of San Benito el Real de Sahagunto was an important monastery during the Middle Ages, reaching its extensive possessions to the lands of Campoo, Liébana, Segovia, Zamora or Palencia, it had jurisdiction over up to 60 priories and issued its own currency, Its abbots were royal advisors and its possessions were inviolable and sacred, the monastery obtained the protection of different nobles and enjoyed royal privileges, becoming a royal pantheon in the time of Alfonso VI, it possessed one of the most extensive and important libraries and scribes of the kingdom of León.
The Royal Monastery of San Benito de Sahagún was an important place of culture and spirituality, it was the seat of an important Theological University that rivaled and came to have the same privileges as the University of Salamanca or Alcalá, from its walls and solemn rooms came countless bishops, prelates and commanders, abbots who rivaled in ecclesiastical and civil power with some sovereigns,
