Short answers, pulled from the story.
Zheng He was a Chinese explorer, admiral, diplomat, and eunuch of the early Ming dynasty, often regarded as the greatest admiral in Chinese history. Born in 1371 as Ma He into a Muslim family in Yunnan, he commanded seven treasure voyages across Asia between 1405 and 1433.
Zheng He commanded seven treasure voyages between 1405 and 1433 under the Yongle Emperor and the later Xuande Emperor. His first voyage departed on the 11th of July 1405 from Suzhou with a fleet of 317 ships and almost 28,000 crewmen.
Zheng He's fleets visited Brunei, Java, Siam, Southeast Asia, India, the Horn of Africa, and Arabia. He brought back novelties including ostriches, zebras, camels, and ivory from the Swahili Coast, and a giraffe from Malindi taken to be a qilin.
The Yongle Emperor conferred the surname Zheng on Ma He during the Chinese New Year on the 11th of February 1404. The honor recognized his defense of Beiping's city reservoir against imperial forces in 1399 and his service in the 1402 campaign to capture Nanjing.
Luo Maodeng's 1597 novel described nine-masted treasure ships about 127 meters long and 52 meters wide, but many scholars dispute this. Excavation of the Treasure Shipyard in Nanjing from 2003 to 2004 and study by Hu Xiaowei in 2018 suggest the largest ships were closer to 70 to 75 meters long.
Zheng He probably died during the treasure fleet's last voyage, around 1433 or 1435, and was buried at sea off the Malabar Coast near Calicut. His tomb at Cattle Head Hill in Nanjing is empty, though his sword and possessions were interred in a Muslim tomb inscribed in Arabic.
The Hongxi Emperor terminated further treasure voyages on the 7th of September 1424, and the Xuande Emperor sent only one more. The voyages violated the Huang Ming Zuxun foundation documents and Confucian principles, and after Zheng He's death officials minimized his record in the histories.