Sir Thomas Gascoigne was a product of developments in English Catholic education that were taking place in the English Catholic schools in northern France during the eighteenth century. It was an education that was clearly influenced by the Enlightenment and an apparent demand from Catholic parents for an education that fitted their sons for active careers as gentlemen in England. His apostasy in 1780 was indirectly a consequence of this education and the aspirations that it fostered. This English Catholic Enlightenment has been noted by many historians who have argued that ‘liberal and “enlightened” notions’ were increasingly beginning to emerge and spread amongst English Catholics in the late eighteenth century, with far reaching consequences for the English Catholic community.

The influence of this enlightened English Catholic education affected a significant number of Gascoigne's contemporaries. By the late eighteenth century a somewhat amorphous movement known as Cisalpinism had emerged that took its name from the Cisalpine Club, formed in 1791 for the purpose of helping the cause of Catholic emancipation by minimising the authority of Rome. They increasingly identified with a concept of Englishness and were sceptical of dogma, miracles and anything that was at odds with empiricism. As an avowed association of Catholic laymen it was not a club to which Gascoigne would have subscribed eleven years after his apostasy, however, he certainly shared their educational experiences and enlightened outlook towards English Catholicism, which were clearly becoming prevalent amongst English Catholics in this period. Geoffrey Scott writing on Sir John Throckmorton (1753–1819) – ‘an outspoken representative’ of the Cisalpine Club and ‘leading English Catholic liberal’ – has specifically argued that Sir Thomas Gascoigne was a ‘like-minded’ gentleman who shared ‘similar European interests’ and religious outlook with this ‘leading member’ of the movement.

With the Cisalpines, too, Gascoigne shared the same educational experience at the same English Catholic colleges at Douai, where they learnt many of the same latitudinarian and enlightened principles with regards their faith in England. Both Gascoigne and his Cisalpine coreligionists emphasised the Englishness of their Catholicism and sought to broaden their ‘own base of consensus with England's predominant Protestant culture, traditions and institutions’, whilst promoting their own form of English (as opposed to Roman) Catholicism.