When the Kangxi Emperor entrusted the Jesuit missionaries with the cartographical survey of his empire, the provinces of Henan, Zhejiang, and Fujian, and the Island of Formosa, fell to the lot of Mailla along with Jean-Baptiste Régis and Roman Hinderer.
When Father Mailla died, in his seventy-ninth year, in Beijing, China, he was buried at the expense of the Qianlong Emperor, many people being present at the obsequies.
Mailla, also, in order to promote the work of the mission, compiled some religious books in Chinese; the most important being lives of the saints, and meditations on the Gospels of the Sundays throughout the whole year.
Being based on the Confucian orthodox text of Zhu Xi, Mailla's Histoire générale gives an idealised account of Chinese imperial history, which should also be read in context of the Rites controversy.
As a result, eighteenth-century Enlightenment leaders discussed China as an example of an ideal secular monarchy, a biased vision supported by Voltaire and opposed by Montesquieu.