So it's worth distinguishing between two broad kinds of foreign holdings in China.
Firstly, treaty ports. The term refers to a series of cities, primarily coastal and riverine, but some inland, which were made open to all international trade by dint of one or more treaties. These cities typically had designated merchant quarters for countries that wished to claim them, which were under the consular jurisdiction of assigned diplomatic officials (which means that those officials were the chief arbitrators in legal cases), but which officially remained Qing (or RoC) territory.
Secondly, there were a series of foreign concessions, settlements which were actually part of foreign territory. Most of these were leaseholds, with the exception of Macau and Hong Kong Island+Kowloon, which were owned in perpetuity by Portugal and Britain, respectively. Being leases, these territories were nominally to revert control to the ruling government of China on the expiry of the lease, but remained the territory of the lease-holders for the duration. I say 'nominally' as in the event, only one such lease expired normally.
Separately, there were some broad regions that were permanently annexed, particularly by Russia on its Siberian and Central Asian frontiers with the Qing Empire, though these are very much beyond the scope of this discussion. There were also certain foreign investment sites, extra port facilities, voluntarily-designated 'open cities', opium receiving stations and so on. The full list of nearly 200 such sites, and some descriptions of all of them, can be found in Robert Neild's China's Foreign Places : The Foreign Presence in China in the Treaty Port Era, 1840-1943 (2015), which was my main source for this post.
Probably the easiest way to present the information is through some tables, so first up we'll have the treaty ports, then the territorial concessions.
(Note: I've used 'Riverine' for any sites where a river directly connected to the sea via Qing/Chinese territory exclusively. Sites for trade with Southeast Asia or Russia, even if located on navigable rivers, have been designated as 'Inland'.)
| Name (Pinyin if applicable, then variants) | Province | Year Opened | Treaty (and foreign signatories) | Type |
|---|---|---|---|---|
| Nerchinsk (Nibcu) | Russian Siberia | 1689 | Treaty of Nerchinsk (Russia) | Inland |
| Kiakhta (Khiagt) | Russian Siberia | 1727 | Treaty of Kiakhta (Russia) | Inland |
| Guangzhou (Canton) | Guangdong | 1757 (made sole maritime entrepôt, but in use earlier) / 1842 (terms modified) | N/A / Treaty of Nanking (Britain) | Coastal |
| Xiamen (Amoy) | Fujian | 1842 | Treaty of Nanking | Coastal |
| Fuzhou (Foochow) | Fujian | 1842 | Treaty of Nanking | Coastal |
| Ningbo (Ningpo) | Zhejiang | 1842 | Treaty of Nanking | Coastal |
| Shanghai | Jiangsu | 1842 | Treaty of Nanking | Coastal |
| Ili | Xinjiang | 1851 | Treaty of Kulja (Russia) | Inland |
| Haikou (Kiungchow) | Guangdong | 1858/60 | Treaty of Tientsin/Convention of Peking (Britain, France, Russia, USA) | Coastal |
| Shantou (Swatow) | Guangdong | 1858/60 | Treaty of Tientsin/Convention of Peking | Coastal |
| Danshui (Tamsui) | Fujian (Taiwan after 1885) | 1858/60 | Treaty of Tientsin/Convention of Peking | Coastal |
| Tainan (Taiwan-fu) | Fujian (Taiwan after 1885) | 1858/60 | Treaty of Tientsin/Convention of Peking | Coastal |
| Penglai (Tängchow) | Shandong | 1858/60 | Treaty of Tientsin/Convention of Peking | Coastal |
| Yantai (Chefoo) | Shandong | 1858/60 | Treaty of Tientsin/Convention of Peking | Coastal |
| Zhenjiang (Chinkiang) | Jiangsu | 1858/60 | Treaty of Tientsin/Convention of Peking | Riverine |
| Nanjing (Nanking)* | Jiangsu | 1858/60 | Treaty of Tientsin/Convention of Peking | Riverine |
| Hankou (Hankow) | Hubei | 1858/60 | Treaty of Tientsin/Convention of Peking | Riverine |
| Yingkou (Newchwang) | Mukden/Fengtian | 1858/60 | Treaty of Tientsin/Convention of Peking | Coastal |
| Zhangjiakou (Kalgan) | Zhili | 1860 | Convention of Peking | Inland |
| Tianjin (Tientsin) | Zhili | 1860 | Convention of Peking | Coastal |
| Kashgar | Xinjiang | 1860 | Convention of Peking | Inland |
| Urga (now Ulaanbaatar) | Mongolia | 1860 | Convention of Peking | Inland |
| Beihai (Pakhoi) | Guangxi | 1876 | Chefoo Convention (Britain) | Coastal |
| Wenzhou (Wenchow) | Zhejiang | 1876 | Chefoo Convention | Coastal |
| Wuhu | Anhui | 1876 | Chefoo Convention | Riverine |
| Yichang (Ichang) | Hubei | 1876 | Chefoo Convention | Riverine |
| Hami (Kumul) | Xinjiang | 1881 | Treaty of St Petersburg (Russia) | Inland |
| Kucheng (Qitai) | Xinjiang | 1881 | Treaty of St Petersburg | Inland |
| Urumqi (Urumchi) | Xinjiang | 1881 | Treaty of St Petersburg | Inland |
| Khovd (Kobdo) | Mongolia | 1881 | Treaty of St Petersburg | Inland |
| Uliassutai | Mongolia | 1881 | Treaty of St Petersburg | Inland |
| Jiuquan (formerly Suzhou) | Gansu | 1881 | Treaty of St Petersburg | Inland |
| Longzhou (Lungchow) | Yunnan | 1887 | Supplementary Convention to 1886 commercial treaty w. France | Inland |
| Manhao | Yunnan | 1887 | Supplementary Convention to 1886 commercial treaty w. France | Inland |
| Mengzi (Mengtse) | Yunnan | 1887 | Supplementary Convention to 1886 commercial treaty w. France | Inland |
| Chongqing (Chungking) | Sichuan | 1876/1890 | Chefoo Convention (pending certain requirements which were not fulfilled until 1889) | Riverine |
| Shashima (Yatung) | Tibet | 1893 | Sikkim Convention (Britain) | Inland |
| Manghuan (Manwyne) | Yunnan | 1894 | 1894 Burmah Convention (Britain) | Inland |
| Hangzhou | Zhejiang | 1895 | Treaty of Shimonoseki (Japan) | Coastal |
| Suzhou (Soochow) | Jiangsu | 1895 | Treaty of Shimonoseki | Riverine |
| Shashi | Hubei | 1895 | Treaty of Shimonoseki | Riverine |
| Simao (Szemao) | Yunnan | 1895 | Additional Convention to 1886 commercial treaty w. France | Inland |
| Hekou (Hokow) | Yunnan | 1896 | Additional Convention to 1886 commercial treaty w. France | Inland |
| Sanshui (Samshui) | Guangdong | 1897 | 1897 Burmah Convention (Britain) | Riverine |
| Jianggen (Kongkun Market) | Guangdong | 1897 | 1897 Burmah Convention | Riverine |
| Wuzhou | Guangxi | 1897 | 1897 Burmah Convention | Riverine |
| Tengchong (Tengyueh) | Yunnan | 1897 | 1897 Burmah Convention | Inland |
| Jiangmen (Kongmoon) | Guangdong | 1902 | 1902 Commercial Treaty (with Britain) | Riverine |
| Changsha | Hunan | 1903 | 1903 Commercial Treaty (with Japan) | Riverine |
| Gartok | Tibet | 1904 | Convention of Lhasa (Britain) | Inland |
| Gyantse | Tibet | 1904 | Convention of Lhasa | Inland |
| Name | Country | Date Ceded | Lease Length (nominal) | End Result |
|---|---|---|---|---|
| Macau/Macao | Portugal | 1557 (original lease) / 26 March 1887 (ceded in perpetuity) | Permanent | Handover to People's Republic of China in 1999 |
| Hong Kong | Britain | 29 August 1842 (HK Island) / 2 November 1860 (Kowloon) / 9 June 1898 (New Territories) | Permanent (Island and Kowloon) / 99 years to 1997 (New Territories) | Lease on New Territories expired; Handover of all of HK to PRC in 1997 |
| Qingdao (Tsingtao) | Germany | 8 March 1898 | 99 years to 1997 | Taken over by Japan in 1914; Handed over to Republic of China in 1922 |
| Lüshun (Port Arthur) | Russia | 27 March 1898 | 25 years to 1923 | Taken over by Japan in 1905 |
| Dalian (Dalny) | Russia | 27 March 1898 | 25 years to 1923 | Taken over by Japan in 1905 |
| Weihaiwei (Weihai) | Britain | 3 April 1898 | Until end of Russian lease on Port Arthur | British retained control after 1905; Handed over to ROC rule in 1930 |
| Kouang-Tcheou-Wan (Guangzhouwan) | France | 10 April 1898 | 99 years to 1997 | Occupied by Japan in 1943; Ceded to ROC in 1945 |
| Lüshun (Ryojun) | Japan | 5 September 1898 (from Russia) / 25 May 1915 (lease extension) | Remainder of 25 years to 1923 (original) / Further extension of 99 years to 2022 (1915) | Annexed by ROC in 1945 |
| Dalian (Dairen) | Japan | 5 September 1898 (from Russia) / 25 May 1915 (lease extension) | Remainder of 25 years to 1923 (original) / Further extension of 99 years to 2022 (1915) | Annexed by ROC in 1945 |
| Qingdao (Tsingtao) | Japan | 7 November 1914 (de facto) | Unspecified | Handed over to ROC in 1922 |
Hope that was of use!