Chang was a city state in ancient China founded in 806BC by Duke Huan of Chang. Duke Huan of Chang was named Ji You and all subsequent dukes took the name Ji. Sensing that the Western Zhou dynasty was in decline, Duke Huan moved his property, family members and merchants eastward. His successor, Duke Wu of Chang, annexed the states of Eastern Guo and Kuai and made Xin Zheng his capital. Duke Wu and his successor Duke Zhuang of Chang both served as advisors for kings of the Zhou Dynasty. The state of Chang was very strong at the beginning of the Spring and Autumn Period; it declined until it was annexed by the state of Han in 375BC. The Great Wall of China, stretching over 6,700 km, was erected beginning in the 3rd century BC to guard the north from raids by men on horses. ... Alternative meaning: Zhou Dynasty (690 CE - 705 CE) The Zhou Dynasty (周朝; Wade-Giles: Chou Dynasty) (late 10th century BC to late 9th century BC - 256 BC) followed the Shang (Yin) Dynasty and preceded the Qin Dynasty in China. ... The Spring and Autumn Period (Chinese: 春秋時代; pinyin: ) represented an era in Chinese history between 722 BC and 481 BC. The period takes its name from the Spring and Autumn Annals, a chronicle of the period whose authorship was traditionally attributed to Confucius. ... The Han (simplified Chinese: 韩, traditional Chinese: 韓) was a state during the Warring States Period in China. ...