Thomas Gage (c. 1597 – 1656) was an English Dominican friar, best known for his travel writing on New Spain and Central America during a sojourn there of over a decade. He closely observes colonial society and culture. On his return to England in 1637 and converted to Anglicanism.
Thomas Gage was the son of the English Catholic gentleman John Gage, from 1622 a baronet, and his wife Margaret. The family were strong Catholics and were intermarried with other Catholic families, including that of Sir Thomas More, the former Lord Chancellor.
The family's Catholicism was practiced behind closed doors. His three older brothers followed in the Catholic tradition. One was the Royalist soldier Colonel Sir Henry Gage (1597–1645), who fought on the Continent for Catholic Spain and eventually in England for Charles I; George was a diplomat and priest; and William was a Jesuit. In fact, there were no fewer than five priests in the family since their half-brothers John and Francis, born of their father's second marriage, were also priests.
John Gage wanted his son Thomas to become a Jesuit, and to this end sent him for a schooling with the Jesuits of the College of St. Omer in the Low Countries and seems to have been an unremarkable pupil. From St Omer he was sent for further education with a view to becoming a Jesuit priest to the English College at Valladolid in Spain. Valladolid was the scene of a good deal of rivalry and bad feeling between the different religious orders, a situation worsened by the temperamental and political tensions between the Spanish and the English. Gage developed a contempt for the Jesuits and like numerous other students of the English College at that period took refuge with a rival establishment, choosing the Dominicans. He joined the Dominicans in Jerez, Spain and his pro-Jesuit father disinherited him.
Having been sent to the English College, Valladolid, in Spain, he showed his first sign of a difficult character when he developed a loathing for the Jesuits who ran the College, left and entered the Dominican, being ordained a priest in. As a Spanish Dominican he served as professor of rhetoric in the convent of Jerez, and then volunteered in 1625 for the mission to the Philippines. There was a hitch. Before his departure a royal decree forbade any foreigner, under severe penalties, to go to the Spanish colonies. Gage was hidden in a barrel and the party of thirty or so Dominican friars sailed from Cadiz, on 2 July 1625.