"Chinese culture did not penetrate Southeast Asia as much as Indian culture because of the fundamental difference in the natures of expansion. Indian penetration was not conquest by a central power. India was politically divided and culturally, racially and linguistically diverse and tolerant. It had a long seafaring and trading history and Indian ships continued to sail to China. After the Zhou conquest of the Shang, Chinese thinking was land-based, centrally directed and to an extent racially motivated. It conquered, annexed and brought cultural unity where possible, administrative unity where not. Its influence spread as far south as Hue in Annam, ‘the pacified south’. Merchants in Southeast Asian and Indo-Chinese ports, on the other hand, spread Indian culture. Exchanges of ambassadors or goods between Indian kingdoms and Southeast Asian polities were made on the basis of equality, whereas Chinese expansion required suzerainty and regular tribute. This was and is an important cultural divide; to the north sinicised, conquered, assimilated, authoritarian; to the south Indianised, trade-minded, expansionary, looking southwest to its cultural origins and north for its biggest customer. Indo-China is so-named for good reason."