The population of Asia in 1500 was five times as big as that of Western Europe (284 million compared with 57 million), and the ratio was about the same in 1600. It was a very large market with a network of Asian traders operating between East Africa and India, and from Eastern India to Indonesia. East of the straits of Malacca,
trade was dominated by China. Indian ships were not sturdy enough to withstand the typhoons of the China sea, and not adequately armed to deal with pirate activity off the China coast….
The Portuguese displaced Asian traders who had supplied spices to Red Sea and Persian Gulf ports
for onward sale to Venetian, Genoese and Catalan traders. But this was only a fraction, perhaps a quarter, of Asian trade in one group of commodities. In addition there was trade within Asian waters in textiles, porcelain, precious metals, carpets, perfume, jewellery, horses, timber, salt, raw silk, gold, silver, medicinal herbs and many other commodities.
Hence, the spice trade was not the only trading opportunity for the Portuguese, or for the other later European traders (Dutch, British, French and others) who followed. Silk and porcelain played an increased role, and in the seventeenth and eighteenth centuries, cotton textiles and tea became very important. There were possibilities of participating in intra–Asian trade as well. In the 1550s to the 1630s this kind of trade between China and Japan was a particularly profitable source of income for Portugal.