China was divided into areas of foreign economic control which were known as spheres of influence.
Britain, France, Germany, and Russia had control over large swaths of Chinese territory which had been taken by means of military attacks or threats to force Chinese authorities to sign unequal treaties. In 1842 Europeans forced the Chinese to sign theTreaty of Nanjing which ended the first Opium War. However, there was an increasing sense of nationalism in China due to a strong reaction to foreign influence. Chinese emperors tried to reduce foreign influence by limiting trading with Europe as they followed a policy of isolationism, since they believed that foreign influences would have a negative effect over China. While European countries grew economically and militarily powerful, China stagnated or declined.