The Tang Dynasty hosted China's only female ruler Wu Zetian. Although even to this day she is a controversial ruler, Wu Zetian's reforms were able to lay the foundation for the later ruler Xiangzong's success. When Xiangzong was in power China was the most prosperous country in the world.
During the time of the Northern Song, there was lots of corruption, this eventually led to the fall of the Northern Song. Zhao Gou, son of the final emperor of the Northern Song, established the Southern Song. Despite the corruption, it is often believed that the Song Dynasty was very prosperous.
Mongolian leader, Tiemuzhen was able to unify all of the internal tribes, because of this Tiemuzhen earned the name Genghis Khan (meaning- ruler of the world). Soon after this Ghengis Khan established the Mongolian Empire. Ghengis Khan's army was able to capture Xixia and the Jin Dynasty, Ghengis Khan continued conquering throughout central Asia and Europe. Many years later Ghengis Khan's grandson, Kublai Khan, acended the throne and established the Yuan Dynasty.
The Ming dynasty was the first dynasty to established a special organisation to prevent corruption among Chinese officials. These ideas and ways of controlling the country were also used all throughout the Qing (Manchu) Dynasty, up until the imperial system was abolished.
The Manchus started when the Jurchen tribal ruler started to conquer enemy Mongol tribes, however, instead of treating them badly he decided to accept them as their own. This allowed Mongols to breed with Jurchens. They eventually conquered the Ming city of Shenyang and made it their capital. Again instead of hurting or terrorising the Ming they decided to let them stay, they even allowed Ming people to become officials. Eventually they captured all of China.
Over time the constant attacking of the wall and the
weather have caused the wall to crumble and decay.
Most of the wall that is seen today was either built or
restored during the Ming dynasty.