<P> The dominance of the Arabs came to a sudden end in the mid-11th century with the arrival of the Seljuq Turks, migrating south from the Turkic homelands in Central Asia . They conquered Persia, Iraq (capturing Baghdad in 1055), Syria, Palestine, and the Hejaz . This was followed by a series of Christian Western Europe invasions . The fragmentation of the Middle East allowed joined forces, mainly from England, France, and the emerging Holy Roman Empire, to enter the region . In 1099 the knights of the First Crusade captured Jerusalem and founded the Kingdom of Jerusalem, which survived until 1187, when Saladin retook the city . Smaller crusader fiefdoms survived until 1291 . In the early 13th century, a new wave of invaders, the armies of the Mongol Empire, swept through the region, sacking Baghdad in the Siege of Baghdad (1258) and advancing as far south as the border of Egypt in what became known as the Mongol conquests . The Mongols eventually retreated in 1335, but the chaos that ensued throughout the empire deposed the Seljuq Turks . In 1401, the region was further plagued by the Turko - Mongol, Timur, and his ferocious raids . By then, another group of Turks had arisen as well, the Ottomans . </P> <P> The Mongol Empire conquered a large part of Asia in the 13th century, an area extending from China to Europe . Medieval Asia was the kingdom of the Khans . Never before had any person controlled as much land as Genghis Khan . He built his power unifying separate Mongol tribes before expanding his kingdom south and west . He and his grandson, Kublai Khan, controlled lands in China, Burma, Central Asia, Russia, Iran, the Middle East, and Eastern Europe . Estimates are that the Mongol armies reduced the population of China by nearly a third . Genghis Khan was a pagan who tolerated nearly every religion, and their culture often suffered the harshest treatment from Mongol armies . The Khan armies pushed as far west as Jerusalem before being defeated in 1260 . </P> <P> The Indian early medieval age, 600 to 1200, is defined by regional kingdoms and cultural diversity . When Harsha of Kannauj, who ruled much of the Indo - Gangetic Plain from 606 to 647, attempted to expand southwards, he was defeated by the Chalukya ruler of the Deccan . When his successor attempted to expand eastwards, he was defeated by the Pala king of Bengal . When the Chalukyas attempted to expand southwards, they were defeated by the Pallavas from farther south, who in turn were opposed by the Pandyas and the Cholas from still farther south . The Cholas could under the rule of Raja Raja Chola defeat their rivals and rise to a regional power . Cholas expanded northward and defeated Eastern Chalukya, Kalinga and the Pala . Under Rajendra Chola the Cholas created the first notable navy of Indian subcontinent . The Chola navy extended the influence of Chola empire to southeast asia . During this time, pastoral peoples whose land had been cleared to make way for the growing agricultural economy were accommodated within caste society, as were new non-traditional ruling classes . </P> <P> The Muslim conquest in the Indian subcontinent mainly took place from the 12th century onwards, though earlier Muslim conquests made limited inroads into the region, beginning during the period of the ascendancy of the Rajput Kingdoms in North India, although Sindh and Multan were captured in 8th century . </P>

What did the civilizations of asia provide the world