Around the year 1200 of this era, the Old World appears as a great plain sparsely inhabited by Siberian Hunters adapted to the cold and relying on the horse and the camel for their survival. In the Far East, the Chinese on the mainland and the Japanese on an archipelago evolved into two sedentary civilizations. Koreans are an offshoot of the Chinese. Chinese occupation of tropical countries (Indochina, Indonesia) proceeded slowly. Chinese junks were sighted in 1404 along African shores but this exploration bore no fruits. On the Asian underbelly, a series of sedentary civilizations (Khmers, Javanese, Vietnamese, Burmese, Indians, Indonesians, Ceylonese) were subject to debilitating climatic conditions that weakened them in the face of invaders. One must emphasize that the political regimes of these countries did not favor progress. For example, the rulers of Korea massively slaughtered the intellectuals of the country in 1498, 1504, 1519, and again in 1545. In Africa, the Sahara insulated effectively various populations that fully adapted to tropical conditions and slowly occupied the totality of the continent. In the Near East, Islam was in full bloom. The Christian empire of Ethiopia was unable to defend its territory in Arabia against the Muslims and turned African and insular. In the West, the flamboyant Greeks strenuously opposed the penetration of Arabs, Turks and Mongols into their territory. They were on the defensive.
Despite the onslaught of the Turks, the Mongols and Timberline, the brilliant cultural revolution started by Muhammad in the 7th century against Christian sedentary Byzantium retained all its vigor: Islam penetrated slowly in Asia. From Persia, the north of India was invaded. The drive east continued south, on the seas, toward Malacca, Indonesia and the Philippines. Islam was also first in Africa and spread down the East coast while the caravans penetrated west along the Niger.
In the central Asiatic plains, the Nomad Empire of Genghis Khan was built. Japan resisted the nomad invasion (1274 and 1281) but the Mongol remained 150 years in China, from 1215 to 1368. The rest of the Asiatic mainland, rich and populous, was not spared: Arabs and Turks had a common enemy. In 1258, the Mongol took Baghdad and the caliphate of the Orient submitted to Hülagü. Foolishly, the crusaders dreamed of making an alliance with the Mongol against the Turk. During the Pax mongolica, Islamic and Nestorian high civil servants of the Khan moved overland to China, where important settlements took place. The Nestorian settlement strongly opposed the installation of a Roman Catholic mission in China, arriving also overland in 1292.
The Western civilization was so poor that the Nomad never cared much to invade it. It was mainly a source of slaves for the Muslims. This Western civilization had two glacis: the Southern Iberian Peninsula, where Islam was slowly forced back to Africa, and the Russian plains, open and easily invaded by the Nomad squadrons. It is from these two glacis that the colonization started. The development of a new weapons system and of maneuverable ships allowed the expansion of Christianity. On land, Greek Orthodoxy overran Siberia with swift horses and firearms, and collided with the Chinese and Ottoman empires. The sea-faring skills acquired by Latin Christianity allowed the conquest of two continents and the exploitation of most of the rest of the world.