During the epoch of the Southern Song Dynasty (1127-1279), Chinese culture went through a glorious time. The Song emperors excelled more as artists and scholars than as politicians. Long before the West gained intimate knowledge of the East, a book called "Description of the Barbarian Countries" was a bestseller in China. The work contained a collection of good knowledge about geography, culture and living standards of the barbarians in Africa and Europe. At that time, social changes took place in China: As a result of book printing, education and literacy reached the masses. Exams for the selection of civil servants replaced the gentry and slowly bur surly produced the caste of the Mandarins. Merchants could still not become civil servants, but many of them got rich. They formed guilds and trade companies and thus exerted a strong influence on commerce.