Tianjin in the context of "Marco Polo Bridge Incident"

A direct-administered municipality (直辖市; Zhíxiáshì; lit. 'direct-administered city'), commonly known as municipality, is a provincial-level administrative division in China. The municipalities are directly affiliated to the central government of China. Although a city by name, a Chinese municipality is more than a city in a traditional sense. It is equivalent to a province as it usually composed of a central urban area and a number of much larger surrounding suburban and rural areas. There are four such municipalities in China: Beijing, Chongqing, Shanghai, and Tianjin.

Beijing, previously romanized as Peking, is the capital city of China. With more than 22 million residents, it is the world's most populous national capital city, as well as China's second largest city by urban area, after Shanghai. It is located in Northern China, and is governed as a municipality under the direct administration of the State Council with 16 urban, suburban, and rural districts. Beijing is mostly surrounded by Hebei Province and neighbors Tianjin to the southeast; together, the three divisions form the Jing-Jin-Ji cluster.

Beijing is a global city and one of the world's leading centres for culture, diplomacy, politics, finance, business and economics, education, research, language, tourism, media, sport, science and technology, transportation, and art. It is home to the headquarters of most of China's largest state-owned companies and houses the largest number of Fortune Global 500 companies in the world, as well as the world's four biggest financial institutions by total assets. It is also a major hub for the national highway, expressway, railway, and high-speed rail networks. For a decade before the COVID-19 pandemic, Beijing Capital International Airport was Asia's busiest airport (2009–2019) and the second busiest airport in the world (2010–2019). In 2020, the Beijing subway was the fourth busiest and second longest in the world. Beijing Daxing International Airport, Beijing's second international airport, is the largest single-structure airport terminal in the world. The city has hosted numerous international and national sporting events, the most notable being the 2008 Summer Olympics and 2008 Summer Paralympics Games. In 2022, Beijing became the first city ever to host both the Summer and Winter Olympics, and also the Summer and Winter Paralympics.

As of 2023, the five largest cities in China by population are Chongqing (31.91 million), Shanghai (24.87 million), Beijing (21.86 million), Chengdu (21.403 million) and Guangzhou (18.827 million). As of 2024, there are 18 megacities (cities with a population of over 10 million), including Chongqing, Shanghai, Beijing, Chengdu, Guangzhou, Shenzhen, Wuhan, Tianjin, Xi'an, Suzhou, Zhengzhou, Hangzhou, Shijiazhuang, Linyi, Dongguan, Qingdao, Changsha and Hefei.

Among them, the total permanent population of Chongqing, Shanghai, Beijing and Chengdu is above 20 million. Shanghai is China's most populous urban area, while Chongqing is its largest city proper, the only city in China with the largest permanent population of over 30 million.

Chongqing is a direct-administered municipality in Southwestern China. Chongqing is one of the four direct-administered municipalities under the Central People's Government, along with Beijing, Shanghai, and Tianjin. It is the only direct-administered municipality located deep inland. The municipality covers a large geographical area roughly the size of Austria, which includes several disjunct urban areas in addition to Chongqing proper. Due to its classification, the municipality of Chongqing is the largest city proper in the world by population, though it is not the most populous urban area.

The municipality of Chongqing is the only Chinese city with a resident population of over 30 million; however, this number includes its large rural population. In 2020, Chongqing surpassed Shanghai as China's largest municipality by urban population; as of 2023, it had an urban population of 22.87 million. The municipality contains 26 districts, 8 counties, and 4 autonomous counties. The city served as the wartime capital for the Republic of China (ROC) during the Second Sino-Japanese War (1937–1945). On 14 March 1997, the current municipality was separated from the surrounding province of Sichuan, with the goal of furthering development in the central and western parts of the country.

The Bohai Sea (Chinese: 渤海; pinyin: Bó Hǎi; lit. 'Bo Sea') is a gulf/inland sea approximately 77,000 km (30,000 sq mi) in area on the east coast of Mainland China. It is the northwestern and innermost extension of the Yellow Sea, to which it connects via the Bohai Strait. It has a mean depth of approximately 18 meters (59 ft), with a maximum depth of about 80 meters (260 ft) located in the northern part of the Bohai Strait.

The Bohai Sea is enclosed by three provinces and one direct-administered municipality from three different regions of China—Liaoning Province (of Northeast China), Hebei Province and Tianjin Municipality (of North China), and Shandong Province (of East China). It is the center of the Bohai Economic Rim, and its proximity to the Chinese capital of Beijing and the municipality of Tianjin makes it one of the busiest seaways in the world. The entrance to the Bohai Sea is considered a part of the territorial sea of the People's Republic of China due to the presence of the Miaodao islands. China declared the Bohai sea to be part of its inland waters in 1958.

Nanjing is the capital of Jiangsu, a province in East China. The city, which is located in the southwestern corner of the province, has 11 districts, an administrative area of 6,600 km (2,500 sq mi), and as of 2021 a population of 9,423,400.Situated in the Yangtze River Delta, Nanjing has a prominent place in Chinese history and culture, having served as the capital of various Chinese dynasties, kingdoms and republican governments dating from the 3rd century to 1949, and has thus long been a major center of culture, education, research, politics, economy, transport networks and tourism, being the home to one of the world's largest inland ports. The city is also one of the fifteen sub-provincial cities in the People's Republic of China's administrative structure, enjoying jurisdictional and economic autonomy only slightly less than that of a province. It has also been awarded the title of 2008 Habitat Scroll of Honor of China, Special UN Habitat Scroll of Honor Award and National Civilized City. Nanjing is also considered a Beta (global second-tier) city classification, together with Chongqing, Hangzhou and Tianjin by the Globalization and World Cities Research Network, and ranked as one of the world's top 100 cities in the Global Financial Centres Index.

As of 2021, Nanjing has 68 institutions of higher learning, including 13 double-first-class universities, ten 111-plan universities, eight 211 universities, and 97 academies. Nanjing University, which has a long history, is among the world's top 10 universities ranked by the Nature Index. The ratio of college students to the total population ranks No.1 among large cities nationwide. Nanjing has the fifth-largest scientific research output of any city in the world. As of 2024, it has been ranked as the world's second most prolific scientific research center in earth and environmental sciences and the world's third most prolific scientific research center in chemistry and physical sciences, according to the Nature Index.

North China (Chinese: 华北) is a geographical region of the People's Republic of China, consisting of five provincial-level administrative divisions, namely the direct-administered municipalities Beijing and Tianjin, the provinces Hebei and Shanxi, and the autonomous region Inner Mongolia (although the four prefectures east of the Greater Khingan Range are sometimes regarded as parts of Northeast China).

Part of the larger region of Northern China (Beifang), it lies north of the Qinling–Huaihe Line, with its heartland in the North China Plain. Most inhabitants here speak variants of Northern Chinese languages such as Mandarin, which includes the Beijing dialect and its cousin variants. The Beijing dialect is largely the basis of Standard Chinese (or Standard Mandarin), the official language of the People's Republic of China. Jin Chinese and Mongolian are also widely spoken due to the political and cultural history of the area.

The Second Opium War (simplified Chinese: 第二次鸦片战争; traditional Chinese: 第二次鴉片戰爭), also known as the Second Anglo-Chinese War or Arrow War, was fought between the United Kingdom and France against the Qing dynasty of China between 1856 and 1860. It was the second major conflict in the Opium Wars, which were fought over the right to import opium to China, and resulted in a second defeat for the Qing and the forced legalisation of the opium trade. It caused many Chinese officials to believe that conflicts with the Western powers were no longer traditional wars, but part of a looming national crisis.

On 8 October 1856, Qing officials seized the Arrow, a British-registered cargo ship, and arrested its Chinese sailors. The British consul, Harry Parkes, protested, upon which the viceroy of Liangguang, Ye Mingchen, delivered most of the sailors to the British on 22 October, but refused to release the rest. The next day, British gunboats shelled the city of Canton. The British government decided to seek redress from China and dispatched a naval force led by Michael Seymour, and France joined in the action, citing as its reason the murder of a French missionary in China. After coordination with each other, the British and French stormed Canton in December 1857. Ye was captured and the governor of Guangdong surrendered. The alliance then moved north to demand a treaty from the Qing court, and on 20 May 1858, captured the Taku Forts, stormed Tianjin, and threatened the capital Beijing. The Qing asked for peace, and signed the Treaty of Tientsin with Great Britain and France in 1858.