The French merchants who foresaw new openings for commerce were also greatly interested in the scheme. Louis XIV. had resolved to send out Jesuit mathematicians to China, where their observations might perfect the knowledge of geography and navigation. He seized the occasion of the visit of the Siamese ambassadors to carry out his design. The Chevalier de Chaumont was appointed ambassador to Siam with the Abbé de Choisy as his co-adjutor with instructions to reside in the Indies until the King of Siam had been converted to Christianity and to work in conjunction with the missionaries to further the great work.
The Abbé who was a most agreeable personage, was bent more on pleasure, than on the giving of instruction but it is not by amenities of character that apostleship is successful.
The Chevalier de Chaumout cast anchor in the Gulf of Siam on September 27th 1687 after a voyage of six months duration. He was accompanied by M. M. Ceberet and La Loubere the chiefs of the deputation, five missionaries and fourteen Jesuits. Father Tachard who had no rank other than that of a mathematician was the life and soul of the party of which he alone imagined he pulled the strings. The stress he lays on the smallest details of the negociations ought at once to make his position suspected. The French were received with every mark of distinction. The King of Siam, laying aside the hauteur of an Asiatic monarch became quite familiar. It was then that the ambassadors become apostles and begged the King to become a Christian.
Their efforts were redoubled on receiving the news that an ambassador had just arrived from Persia to convert the King to Islam. The Missionaries in their zeal and desire to gain so illustrious a convert, overstepped the limits of his favour. The Chevalier du Chaumont under instructions from them and from Faulcon (who though animated by the same zeal had yet other motives) never ceased pointing out to the King on every possible occasion, that it was the ardent wish of Louis XIV that he should embrace Christianity.
Narai, wearied by his importunity, asked what had led the King of France to believe that he had wished to become a Christian.
The following was the King's reply from the memory of those who were present and who were desirous of his conversion. Faulcon himself acted as interpreter.