Ignatius Loyola. July 3. Founder of Jesuit Order (1491–1556).
Isidore the Ploughman (Isidro el Labrador). May 15. Patron of Madrid and of farmers (born ca. 1110–1170).
James the Great. July 25. Apostle; patron of Spain and of pilgrims to Jerusalem (died 42).
Januarius. September 19. Patron of Naples (died 305).
Jerome. September 30. Patron of scholars. One of the four Latin Fathers (342–420).
John the Baptist. June 24, or Midsummer Day.
John the Evangelist. December 27 (died 101).
Joseph. March 19.
Julian Hospitator. January 9. Patron of hospitals (died 313).
Justina of Padua. October 7. One of the patrons of Padua and Venice (died 303).