In the 1st year (1403) of the Yongle reign period, the Chinese court sent eunuch Yin Qing to Guli (Calicut) on the southwestern coast of India to present colored silk as a gift to its king. The latter sent an envoy with Yin Qing on his return to China. Four years later, Zheng He went to Calicut as an envoy, and presented the king with an imperial order conferring titles and a silver seal upon him, at the same time, issuing official hats and robes to Calicut dignitaries. In the 21st year(1422) of the Yongle reign period, envoys from Calicut, together with ones from Hormuz and other states, totaling 1,200, traveled to China. Being absent from the capital at the time of their arrival, the emperor instructed the crown prince to entertain the envoys as soon as they arrived, and give them gifts upon their departure. Moreover, preferential prices should be paid for the native products they had for sale.
 
The area of Aden and Tianfang at the southern part of the Arabian Peninsula is the Islamic holy land. It took three months to travel from Calicut in a southwesterly direction to reach this area. The Ming Shi says, "In the 5th year (1430) of the Xuande reign period, Zheng He went to the Western Ocean as the (imperial) emissary. He sent out a detachment to Calicut. After learning that Calicut was to send people to Tianfang, he dispatched some of his own men on the same ships with gifts. The round trip lasted a year  The king of Tianfang sent ministers with the Chinese emissaries on their return to pay tribute. Pleased, Emperor Xuanzong bestowed handsome gifts (on them)."
 
The inclusion of a large number of troops in Zheng He's parties was to defend the missions against pirates. The entry on Ceylon in the Ming Shi says, "Zheng He got to this place on his way to the Western Ocean as an imperial emissary. Its king Alakeswara plotted against his life. Alerted, (Zheng) He moved to another country. Moreover, the king was not friendly to his neighbors, often sending men to intercept and rob emissaries. As a result, various foreign countries suffered. When (Zheng) He passed through the place on his way back, the king lured him into the country, and sent 50,000 troops to block his retreat. (Zheng) He led 2,000 foot soldiers, and, following a precipitous trail, seized the lightly defended capital city. He then captured the king, and his wife and children, as well as his chieftains. When the captives were brought to the Ming court, the ministers called for the death penalty. The emperor, however, decided to release the captives, on the grounds that he had acted out of ignorance, and provided them with food and clothing." Zheng He visited Ceylon again during his last (7th) voyage.
   
Zheng He visited the state of Sumatra three times. When he was there in the 13th year (1415) of the Yongle reign period, he was attacked by Suganla, the brother of Sumatra's king. Suganla "was enraged because he was not a recipient of the gifts (from the Chinese emperor), so he led tens of thousands of men to attack the Chinese envoy. Zheng He led his men and local people in repulsing the attackers, and chased them to the state of Nanboli, where they were captured." Zheng He was able to receive support from local people of Sumatra because he only fought in self-defense
 
Still another example is Zheng He's fight to wipe out a pi- rate band headed by Chen Zuyi in the Strait of Malacca. "The pirates robbed passengers and ships that passed through the strait. Because traders were blocked, communication with various countries was cut off, and only Annam, Champa, Zhenla (Cambodia), Siam and Ryukyu paid tribute as usual." In the 5th year (1407) of the Yongle reign period, Zheng He led his men in wiping out these pirates, and established a fort at Palembang to keep the Straits of Malacca open, under the command of Shi Jinqing, an overseas Chinese of Guangdong origin.