Yan (state) in the context of "Ji (state in modern Beijing)"

Qin's wars of unification were a series of military campaigns launched in the late third century BC by the state of Qin against the other six states remaining in China – Han, Zhao, Yan, Wei, Chu and Qi. Between 247 and 221 BC, Qin had developed into the most powerful of China's Seven Warring States that coalesced in the wake of the declining Zhou dynasty, which had been reduced to a weak and merely ceremonial position during the Warring States period. In 230 BC, Ying Zheng, the King of Qin, began the sequence of campaigns that would bring the Warring States period to a close, setting out to conquer each of the six states one by one. This was completed in 221 BC with the fall of Qi, which further led to a more centralised form of government replacing the fengjian system of the Zhou dynasty. Ying Zheng declared himself the First Emperor – or Shi Huangdi – of a unified China under the Qin dynasty.

The Liaodong or Liaotung Peninsula (simplified Chinese: 辽东半岛; traditional Chinese: 遼東半島; pinyin: Liáodōng Bàndǎo) is a peninsula in southern Liaoning province in Northeast China, and makes up the southwestern coastal half of the Liaodong region. It is located between the mouths of the Daliao River (the historical lower section of the Liao River) in the west and the Yalu River in the east, and encompasses the territories of the whole sub-provincial city of Dalian and parts of prefectural cities of Yingkou, Anshan and Dandong.

The word "Liaodong" literally means "Liao region's east", referring initially to the Warring States period Yan commandery of Liaodong, which encompassed an area from modern Liaoning-Jilin border in the north to the Chongchon River on the Korean Peninsula in the south, and from just east of the Qian Mountains to a now-disappeared large wetland between the western banks of middle Liao River and the base of Yiwulü Mountain, historically known as the "Liao Mire" (遼澤, Liáo zé) roughly in between the modern Xinmin, Liaozhong, Tai'an, Panshan and Beizhen). The modern usage of "Liaodong", however, simply refers to the half of Liaoning province to the left/east bank of the Liao/Daliao River.

Zhao (traditional Chinese: 趙; simplified Chinese: 赵) was one of the seven major states during the Warring States period of ancient China. It emerged from the tripartite division of Jin, along with Han and Wei, in the 5th century BC. Zhao gained considerable strength from the military reforms initiated during the reign of King Wuling, but suffered a crushing defeat at the hands of Qin at the Battle of Changping. Its territory included areas in the modern provinces of Inner Mongolia, Hebei, Shanxi and Shaanxi. It bordered the states of Qin, Wei, and Yan, as well as various nomadic peoples including the Hu and Xiongnu. Its capital was Handan, in modern Hebei province.

Zhao was home to the administrative philosopher Shen Dao, Confucian Xun Kuang, and Gongsun Long, who is affiliated to the school of names.

The Seven Warring States or Seven Kingdoms (traditional Chinese: 戰國七雄; simplified Chinese: 战国七雄; pinyin: zhàn guó qī xióng) were the seven leading hegemonic states during the Warring States period (c. 475 to 221 BC) of ancient China:

• Han (韓/韩), defeated by Qin in 230 BCE
• Zhao (趙/赵), defeated by Qin in 228 BCE
• Wei (魏), defeated by Qin in 225 BCE
• Chu (楚), defeated by Qin in 223 BCE
• Yan (燕), defeated by Qin in 222 BCE
• Qi (齊/齐), defeated by Qin in 221 BCE
• Qin (秦)

During the Eastern Zhou dynasty, the weakened Zhou central sovereignty quickly lost control of its confederate vassal states, and the numerous autonomous states began overreaching and expanding their political ambitions via diplomacy and warfare, sparking a period of chaotic conflicts known as the Spring and Autumn period. After most of the smaller, weaker states were conquered and annexed by larger states, the geopolitical landscape eventually became dominated by seven most powerful states, and wars became increasingly pitched and violent. Over the Warring States period, many of the seven states underwent bureaucratic and military reforms in order to mobilise resources on a greater scale. This led to an intensification of warfare over the period, but also led to significant economic and cultural developments.

Hebei is a province in North China. It is China's sixth-most populous province, with a population of over 75 million people. Shijiazhuang is the capital city. It borders Shanxi to the west, Henan to the south, Shandong and Liaoning to the east, and Inner Mongolia to the north; in addition, Hebei entirely surrounds the direct-administered municipalities of Beijing and Tianjin on land. Its population is 96% Han Chinese, 3% Manchu, 0.8% Hui, and 0.3% Mongol. Varieties of Chinese spoken include Jilu Mandarin, the Beijing dialect of Mandarin, and Jin Chinese.

During the Spring and Autumn and Warring States periods (771–226 BC), the region was ruled by the states of Yan and Zhao. During the Yuan dynasty (1271–1368), the region was called Zhongshu. It was called North Zhili during the Ming dynasty (1368–1644), and simply Zhili during the Qing dynasty (1644–1912). The modern province of Hebei was created in 1928. Five UNESCO World Heritage Sites can be found in the province: the Great Wall of China, Chengde Mountain Resort, Grand Canal, Eastern Qing tombs, and Western Qing tombs. It is also home to five National Famous Historical and Cultural Cities: Handan, Baoding, Chengde, Zhengding and Shanhaiguan.

Jicheng, less commonly called Ji and Yanjing, was an ancient city in northern China, which has become the longest continuously inhabited section of modern Beijing. It has been known by numerous other names over its long history, usually in reference to the changing territories it presided over. Historical mention of Ji dates to the founding of the Zhou dynasty in about 1045 BC. Archaeological finds in southwestern Beijing where Ji was believed to be located date to the Spring and Autumn period (771–476 BC). The city of Ji served as the capital of the ancient states of Ji and Yan until the unification of China by the Qin dynasty in 221 BC. Thereafter, the city was a prefectural capital for Youzhou through the Han dynasty, Three Kingdoms, Western Jin dynasty, Sixteen Kingdoms, Northern Dynasties, and Sui dynasty. With the creation of a Ji Prefecture in present-day Tianjin during the Tang dynasty, the city of Ji became more exclusively referenced as Youzhou or by its subsequent renamings including Yanjing. Youzhou was one of the Sixteen Prefectures ceded to the Khitans during the Five Dynasties. The city then became the southern capital of the Liao dynasty and then the main capital of the Jurchen Jin dynasty. In the 13th century, Kublai Khan built a new capital city for the Yuan dynasty adjacent to Ji to the north. The old city of Ji became a suburb to Khanbaliq/Dadu, whose site was developed under the Ming and Qing dynasties into modern Beijing.