Chinese records are some of the earliest reliable records which tells us of early Southeast Asia. In the 3rd century, A.D. when the Chinese empire was divided into three kingdoms, the Southern kingdom of Wu sent a mission to Southeast Asia to report on the political situation there. They wrote of more than a hundred kingdoms in what they referred to as the 'Southern Seas'. The mission had important consequences. It encouraged many more Southeast Asian states to open official relations with China. At first, those who sent missions to China most frequently were mainly from modern Vietnam, Cambodia, Thailand and the Malay Peninsula. But later, the kingdoms of Java and Sumatra noted the profits of the China trade and sent missions too.

This trade became increasingly important as the Chinese became more and more ardent in their new Buddhist faith. The famous Buddhist monk I-Tsing used Chien-Ch'a (Kedah) and Lang-Chia-Shu (Langkasuka) as stopping points on his pilgrimage to India. Because of Buddhism, they began to use incense, and the best incense was made from the aromatic woods found in Southeast Asia. They specially valued some of the objects of worship to be found in the Buddhist centres of the region, both in India and Sri Vijaya.

In this way, new links were established and the trade expanded rapidly. The reunification of China by the Sui and T'ang dynasties in the 7th century greatly increased this trade - the power and wealth of the newly reunified China was quickly appreciated in Southeast Asia, and most of the kingdoms in the area sought to establish official relations with China. T'ang China was the richest country at that time and attracted traders from all over the world, both by land and by sea. By the 10th century, when the T'ang dynasty collapsed, a trading system evoplved whereby officials at the southern ports welcomed the foreign trading missions and determined their tributary status, while local Chinese merchants handled the trade under supervision. In this way, both imperial and private interests were served and a new era of trading was opened. China became a very important market for Southeast Asian goods and the trade brought wealth to the region. As time went on, the Chinese not only traded in goods to and from China, but also became some of the middlemen in the trade between different parts of Southeast Asia. When the Mongols conquered China and founded the Yuan dynasty, they found the trade necessary for imperial revenue. They even went so far as to organise an expedition to Java in 1293 to demonstrate the power of China, sending a fleet of a thousand ships carrying 20,000 men.

China began to have great political influence. This was not in terms of changing the local forms of government or the ideas of government. What was significant was the very near presence of China's power. Although China did not really use this power against Southeast Asia (except for the Mongol expedition to Java), its potential power was often a factor in local politics. This was particularly true during the 15th century, during the Ming dynasty, when Chinese fleets sailed several times down the South China Sea. These expeditions of the famous Admiral Cheng Ho just one century before the arrival of the Europeans, marked the peak of Chinese relations with Southeast Asia. The fleets demonstrated Chinese power, Cheng Ho intervened in local politics and the tributary system was reinforced. Even though the expeditions were abandoned and the policy reversed after 30 years, the impact of China's power was tremendous.