March 30, 1656
Boym and Zheng set off on a journey back to China with the Enxobregas galleon. It is fraught with dangers - four out of nine traveling companions die on board the ship of disease and exhaustion.
November 6, 1656
Boym and Zheng reach the Portuguese port of Goa on the Midwest Coast of India. Here, Boym receives information about the disastrous situation of Emperor Yongli, whose troops now control only a modest part of the southwestern lands of the empire. He receives a letter from the Macao Provincial informing him that due to the Portuguese trade relations with the Manchus, his return to Macau is highly undesirable.
Beginning 1657
In early 1657, the port of Goa was surrounded by the ships of the Dutch trading company VOC, making it impossible to sail by boat. However, Boym and Zheng do not give up and walk through India, following an unknown route. Having reached the east coast of India, they board a Muslim ship bound for the Kingdom of Siam (today, Thailand).
Beginning 1658
Boym and Zheng reach Ayutthaya, the capital city of the Kingdom of Siam. Here they find another letter, this time from the Senate of Macau. It contains the demand for them not to go back to the colony, where they are now considered persona non-grata. Their trip through the Malay Peninsula, including close encounters with tigers, elephants, and rhinos, he describes in his letter sent to Rome.
May 1658
The companions learn that the Ming court remains in the Guangxi Province of China, which borders with the Kingdom of Tonkin (Northern Vietnam). Boym decides to reach it, and therefore both travelers get on a Chinese pirate junk. Although himself ready for the highest sacrifice, the Polish Jesuit is also very conscious of how his mission presents an ever-growing danger not only for him personally. He realizes it also jeopardizes the situation of the entire Jesuit community and the interests of the Portuguese Crown, the primary protector of Jesuit missions in Asia. However, his honor and his sense of loyalty do not permit him to turn back.
August 10th, 1658
After two months of perilous journey on a small junk around the Indochina Peninsula, Boym and his faithful companion Zheng reach Tonkin. From here, Boym sends his last letter to Europe addressed to the Grand Duke of Tuscany, Ferdinando II de Medici, his protector during the period of waiting to be seen by the Pope.
In this letter dated November 20th, Boym, with great optimism, speaks of the recent successes of the Ming army and seems to have faith in the ultimate victory of the Ming dynasty. Notwithstanding Tonkin, Jesuit Mission superior`s, Father Onofrio Borges` insistence to make him renounce further journey, Michał Boym and Andreas Zheng leave Tonkin on foot.
February 16th, 1659
Having obtained the permission of the local authorities, the voyagers cross the border with China. On the Chinese side, the news of the Manchu army overtaking farther territories reaches them. As a result, they are cut off from the place where Emperor Yongli`s court is stationed. They decide to return to Tonkin. From there, try another route via Burma to reach, at last, the goal of so many years of peregrination. On the way there, they receive the depressing news of the death of Chancellor Pang and Father Koffler. Reaching the border with Tonkin, they meet with the refusal to enter the kingdom.
August 22nd, 1659
Michał Boym dies of exhaustion and is buried by the only witness to his death, his loyal co-traveler, Andreas Zheng, somewhere along the royal tract from Hanoi to Nanning, the capital city of Guanxi. On the top of his burial, a simple cross with a tribute in Chinese is placed. The exact site of his sepulture is unknown till this day.