Ricci was an Italian Jesuit missionary to China who came to love his adopted country so much that he decided never to leave. His respectful and genuine assimilation into Chinese culture opened doors that enabled him to establish the Church in what was then one of the most closed societies in the known world.
Ricci was born in Macerata, then part of the Papal States. He received a good classical education, followed by a two-year study of the law in Rome. Against the wishes of his father, who banned talk of religion in their house, Ricci became a Jesuit at the age of 19 and entered the Roman College, where he studied philosophy, theology, mathematics, cosmology and astronomy.
In 1577 Ricci applied to serve as a missionary in the Far East. The first stage of his journey was a six-month ocean voyage in 1578 from Lisbon, Portugal, to Goa, a city on the western coast of India that was then a Portuguese colony. There, he taught, studied, and in 1580, was ordained as a priest. In 1582 he was sent to Macao, a port city on the South China Sea, for the second leg of his journey. At the time, Macao was a Portuguese trading post, the only place in China that Christian missionaries had ever visited (there had been sporadic attempts over the years to go farther, but none of them panned out). When he arrived there, Ricci joined Michele Ruggieri, another Italian Jesuit who had been sent to Macao three years earlier to study Chinese as a first step toward the hoped-for expansion of the Jesuit mission deeper into China. Ricci, too, settled in at Macao and applied himself to the task of learning the Chinese language, customs, art, literature and philosophy. It took a little while, but he became fluent in all of them.
Ruggieri, of course, is your bonus R person. He got to China first, which was awesome (given how little was known to Europeans about the country, it must have been a lot like being a twentieth-century astronaut at the beginning of the space program), but he loses top billing because eventually he went back home. Not Ricci. To him, China became home.
From their base in Macao, Ricci and Ruggieri traveled to Canton and Zhaoqing, the major cities of Guangdong province, to scope out a site for a Jesuit mission. Fortunately for them, the governor of Zhaoqing had heard of Ricci's skills as a mathematician and was intrigued. At his invitation, Ricci and Ruggieri came to live in Zhaoqing in 1583. The following year, Ricci repaid his hosts by creating the first European-style map of the world written in Chinese. As up until that time, the Chinese concept of a "map of the world" was a map of the Chinese provinces, with a few other countries tossed in helter-skelter outside its borders, Ricci's map predictably caused quite a stir. China was huge, but the world was much, much huger.
During their stay in the city, Ricci and Ruggieri also compiled a Chinese-Portuguese dictionary, the first such book translating Chinese into any other language. They developed their own method for transliterating Chinese symbols into the European alphabet.
(a page of the dictionary)
In 1588 Ruggieri returned to Italy to try to persuade the Pope to send an embassy to the Chinese Emperor. He never succeeded in this, and a decline in his health prevented him from ever returning to China as he had intended. He died in Salerno in 1607.
Meanwhile, Ricci remained in Zhaoqing until 1589, when the new viceroy of the city expelled him. He obtained permission to relocate to Shaoguan, in the north of the province, and to reestablish his mission there while he continued to travel around. In 1597, the Jesuits appointed Ricci to be Major Superior of the Chinese mission. He moved briefly to Beijing in 1598, and from there to Nanjing and then Suzhou. At some point along the way, he participated in proving scientifically that the "Cathay" to which Marco Polo had traveled 300 years earlier was, in fact, China. Because Polo had arrived in Cathay by an overland route and everyone else since then had come by sea, there had been some doubt as to whether China and Cathay were actually the same place.
To the insular Chinese, all non-Chinese people were "barbarians," and presumably those who came to China to try to convert them to a Western religion were a particularly unwelcome species. But as it happened, at the time China was experiencing a sort of Dark Ages in scientific and mathematical knowledge, and Ricci was an extremely well-educated barbarian. And while he made no secret of his underlying religious mission, he also seemed genuinely happy to teach his new friends trigonometry, astronomy, world geography, and anything else that he knew and they didn't. He fully adapted to their customs, dressing as a Chinese scholar (see above illustration). He introduced them to the trigonometric and astronomical tools he had brought with him. He translated mathematical works, including the fist six books of Euclid's Elements, into Chinese. In short, because of his unique combination of intellect and personality, Ricci gradually grew on the Chinese people. His motives were aboveboard, and he gave more than he got.
By 1601, he had achieved such status that he was invited by the Imperial Emperor to become a mathematical advisor to the court, thus becoming the first foreigner to enter the Forbidden City (he was given free rein there, although he never actually met the Emperor). Ricci established the first Catholic church in Beijing. He mingled with the intelligentsia and with high government officials, and succeeded in converting a number of them. When he died in 1610, special dispensation was granted by the Emperor for him to be buried in Beijing, in a Buddhist temple constructed for that purpose.