It was a stunning reversal of fortune for a country that in Chinese eyes was the civilized center of the entire world in their terms, the Middle Kingdom. Because of Chinese economy, chinese population were 100 million people in 1685 and in around 1853 population was increased to 430 million. Because of growth of population, the state was increasingly unable to effectively perform its many function, such as tax collection, flood control, social welfare and public security.
Opium was a massive addiction problem in China. It was recognized a mounting problem on any levels. Because opium importation was illegal, it had tone smuggled into china, thus flouting Chinese law. They were many many corrupted official at that period of time. Because of that addiction, it caused a serious economic imbalance.