Better water transportation and greater precision in numerical calculations intensified interactions within Eurasia and Africa and consolidated the Old World Web. Under the Song dynasty, the Chinese economy became commercialized, The Grand Canal not only connected nearly 100 million people in the Chinese market but also enabled the concentration of material resources. Kublai Khan’s conquest of China then unified the Chinese market with the rest of Eurasia and spread Chinese influence in an unprecedented fashion. When the Ming dynasty retook China from the Mongol Empire, China prioritized internal peace and stability at the expense of commercial imperial expansion.

The absence of navigable waterways inhibited Southwest Asian and Muslim economic expansion into the rural majority. However, several factors still allowed Islam to spread its influence in a limited way. Turkic advances into the Muslim heartland and Mongol conquest of Persia, Mesopotamia, and part of Syria gave rise to mysticism and a distinct style of secularism that encouraged scientific advancement. The mysticism, secularism, and military enterprise combined to expand Islam rapidly over a 500-year period. The Ottoman Empire increased contact and trading with West Africa and subsumed the Malay Peninsula and Indonesian islands under Muslim control.