Francis Xavier (born Francisco de Jasso y Azpilicueta; Latin: Franciscus Xaverius; Basque: Frantzisko Xabierkoa; French: François Xavier; Spanish: Francisco Javier; Portuguese: Francisco Xavier; 7 April 1506 – 3 December 1552), venerated as Saint Francis Xavier, was a Navarrese Catholic missionary and saint who was a co-founder of the Society of Jesus.

Born in Javier (Xavier in Old Spanish and in Navarro-Aragonese, or Xabier (Basque language for "new house")), Kingdom of Navarre (in present-day Spain), he was a companion of Ignatius of Loyola and one of the first seven Jesuits who took vows of poverty and chastity at Montmartre, Paris in 1534. He led an extensive mission into Asia, mainly in the Portuguese Empire of the time and was influential in evangelization work, most notably in India. Although some sources claim that the Goa Inquisition was proposed by Francis Xavier, his letter to the king of Portugal, John III, asked for a special minister whose sole office would be to further Christianity in Goa. He also was the first Christian missionary to venture into Japan, Borneo, the Maluku Islands, and other areas. In those areas, struggling to learn the local languages and in the face of opposition, he had less success than he had enjoyed in India. Xavier was about to extend his missionary preaching to China when he died on Shangchuan Island.

He was beatified by Pope Paul V on 25 October 1619 and canonized by Pope Gregory XV on 12 March 1622. In 1624, he was made co-patron of Navarre. Known as the "Apostle of the Indies" and "Apostle of Japan", he is considered to be one of the greatest missionaries since Paul the Apostle. In 1927, Pope Pius XI published the decree "Apostolicorum in Missionibus" naming Francis Xavier, along with Thérèse of Lisieux, co-patron of all foreign missions. He is now co-patron saint of Navarre, with Fermin. The Day of Navarre in Navarre, Spain, marks the anniversary of Francis Xavier's death, on 3 December 1552.