In the field of international relations, a sphere of influence (SOI) is a spatial/geographic region, or set of polities or nations, over which a leader nation state or other geopolitically powerful organisation has a level of cultural, economic, military, or political influence or exclusivity.
While there may be a formal alliance or other treaty obligations between the influenced and influencer, such formal arrangements are not necessary for a sphere to exist. Influence can be had through the use of hard as well as soft power. Similarly, a formal alliance does not necessarily mean that one country lies within another's sphere of influence. Historically, strong or strict exclusivities within spheres of influence, has often led to or been associated with higher levels of global conflict and tension between such spheres. Inter-sphere trade, interdependence and communication, on the other hand, have spawned periods of relative peace – as have periods where spheres of influence have been more weakly enforced and international associations more voluntary.
In extreme cases, a country or community within the "sphere of influence" of another, more powerful nation state, may become a client state or a functional subsidiary of that state -- serving in effect as a satellite state or de facto colony. This was the case, in the decades following the end of World War II, with the Soviet Union (through dominant power Russia) and smaller members of the Eastern Bloc (eg, the Baltic states; such power relations arguably exist in Belarus today). The system of spheres of influence, under which regions are divided amongst powerful nations, who then influence or intervene in the affairs of small nations in their region, continues to the present. Geopolitical power relations are often analyzed using notions of regional or global superpowers, great powers, and/or middle powers.
Sometimes different portions of a single country can fall into different spheres of influence, or a nation may fall into different spheres of influence depending on the factor being influenced (eg, trade, or cultural, influence). In the 19th century, the buffer states of Iran and Thailand, lying between the empires of Britain, France, and Russia, were divided between the spheres of influence of those three international powers. Likewise, after World War II, Nazi Germany was divided into four occupation zones, three of which later consolidated into West Germany and the remaining one became East Germany, the former a member of NATO and the latter a member of the Warsaw Pact.
Historical remnants Before modern international relations were established in Europe, many powerful states had subordinate tributary states, in which the less powerful states or kingdoms submit to the payment of tribute in order to maintain a degree of independence.
As European nation-states explored and sought to claim large parts of Africa, Asia, and the Pacific, often under the aegis of international law, a language of "colonies", "protectorates", "spheres of influence", and "empires" emerged. The international relations thus characterized bespoke usefructory relations of military and political domination. At the same time, the exploration of the globe, the "spread of civilisation", the conveyance of enlightenment and western values, and the promotion (over time) of proto-democratic models of government, were seen as part of the "gift" of such empires to territories and peoples unfamiliar with Europe, its people and ideas.
Many areas of the world are still joined to a "mother country", a European nation, by common heritage, demography, and cultural influence inherited while such powers had clearer spheres of influence, even if such nations no longer exert any real political control over their former colonies. Examples include the Anglosphere, Arab world, Batavosphere, Persosphere, Eurosphere, Francophonie, , Germanosphere, Indosphere, Hispanidad, Latin Europe/Latin America, Lusophonie, Turkosphere, Sinosphere, Slavisphere, Malay world, post-Soviet states, and many others.
History
Early United States (1820s)
Alexander Hamilton, first U.S. Secretary of the Treasury, aimed for the United States to establish a sphere of influence in North America. Hamilton, writing in the Federalist Papers, harboured ambitions for the US to rise to world power-status, and over time gain sufficient strength to aver or even expel European powers from the Americas. The US, under this thinking, would exercise regional dominance throughout the territory and seas of North America, and amongst all nations extant in such geographic space; this was ambitious, as most of the New World was still governed through colonial arrangements by powerful European nations (empires) at the time.
An elaboration of this doctrine, later dubbed the 'Monroe Doctrine', was formalized under President James Monroe (in office for two terms from 1817–1825), who asserted that the New World was to be established as part of the American sphere of influence, and concomitantly be removed from the encroachment of European power. As the US emerged as a world power, few nations dared to trespass on this sphere (a notable exception occurred with the Soviet Union and the Cuban Missile Crisis).
Even in 2018, US Secretary of State Rex Tillerson referenced to the Monroe Doctrine as he touted the US as the region's preferred trade partner over other nations with other, more distant spheres of geographic influence (such as China).
New Imperialism era (late 1800s – early 1900s)
For Siam (Thailand), Britain and France signed an agreement in 1904 whereby the British recognised a French sphere of influence to the east of the River Menam's (Chao Phraya River) basin; in turn, the French recognised British influence over the territory to the west of the Menam basin and west of the Gulf of Thailand. Both parties disclaimed any idea of annexing Siamese territory.
In the Anglo-Russian Convention of 1907, Britain and Russia divided Persia (Iran) into spheres of influence, with the Russians gaining recognition for influence over most of northern Iran, and Britain establishing a zone in the southeast.British Documents on the Origins of the War 1898–1914, Volume IV, The Anglo-Russian Rapprochement 1903-7. Edited by G. P. Gooch and H. Temperley. Her Majesty's Stationery Office, London 1929. p618-621. Appendix IV – Revised Draft of Agreement Concerning Persia, Sent to Sir A. Nicholson by Sir Edward Grey on June 6, 1907
China In China, during the mid 19th and 20th centuries (known in China as the "century of humiliation"), Great Britain, France, Germany, Russia, and Japan held special powers over large swaths of Chinese territory based on securing "nonalienation commitments" for their "spheres of interest"; only the United States was unable to participate due to their involvement in the Spanish–American War. These spheres of influence were acquired by forcing the Qing government to sign "unequal treaties" and long-term leases.
In early 1895, the French laid claim to a sphere in Southwest China. By December 1897, German Kaiser Wilhelm II declared his intent to seize territory in China, precipitating the scramble to demarcate zones of influence in China. The Germans acquired, in Shandong province, exclusive control over developmental loans, mining, and railway ownership, while Russia gained a sphere over all territory north of the Great Wall, in addition to the previous tax exemption for trade in Mongolia and Xinjiang, economic powers similar to Germany's over Fengtian, Jilin, and Heilongjiang provinces. France gained a sphere over Yunnan, as well as most of Guangxi and Guangdong provinces; Japan over Fujian province; and the British over the whole Yangtze River Valley (defined as all provinces adjoining the Yangtze river as well as Henan and Zhejiang provinces), parts of Guangdong and Guangxi provinces, and part of Tibet. Only Italy's request for Zhejiang province was declined by the Chinese government. These do not include the lease and concession territories where the foreign powers had full authority.
The Russian government militarily occupied their zone, imposed their law and schools, seized mining and logging privileges, settled their citizens, and even established their municipal administration on several cities, the latter without Chinese consent.
The powers (and the United States) might have their own courts, post offices, commercial institutions, railroads, and gunboats in what was on paper Chinese territory. However, the foreign powers and their control in some cases could have been exaggerated; the local government persistently restricted further encroachment. The system ended after World War II.
On September 6, 1899, US Secretary of State John Hay sent notes to the major powers (France, Germany, Britain, Italy, Japan, and Russia), asking them to declare formally that they would uphold Chinese territorial and administrative integrity and would not interfere with the free use of the treaty ports within their spheres of influence in China, as the United States felt threatened by other powers' much larger spheres of influence in China and worried that it might lose access to the Chinese market should the country be officially partitioned. Although treaties made after 1900 refer to this "Open Door Policy", competition among the various powers for special concessions within China for railroad rights, mining rights, loans, foreign trade ports, and so forth, continued unabated,Sugita, Yoneyuki, "The Rise of an American Principle in China: A Reinterpretation of the First Open Door Notes toward China" in Richard J. Jensen, Jon Thares Davidann, and Yoneyuki Sugita, eds. Trans-Pacific relations: America, Europe, and Asia in the twentieth century (Greenwood, 2003) pp. 3–20 online . with the US itself contradicting the policy by agreeing to recognize the Japanese sphere in the Lansing–Ishii Agreement.
World War II (1939–1945)
Empire of Japan
For another example, during the height of its existence in World War II, the Empire of Japan had quite a large sphere of influence. The Japanese government directly governed events in Korea, Vietnam, Taiwan, and parts of Mainland China. The "Greater East Asia Co-Prosperity Sphere" could thus be quite easily drawn on a map of the Pacific Ocean as a large "bubble" surrounding the islands of Japan and the Asian and Pacific nations it controlled.
Molotov–Ribbentrop Pact According to a secret protocol attached to the Molotov–Ribbentrop Pact of 1939 (revealed only after Germany's defeat in 1945), Northern and Eastern Europe were divided into Nazi and Soviet spheres of influence:Text of the Nazi-Soviet Non-Aggression Pact , executed August 23, 1939
In the north, Finland, Estonia, and Latvia were assigned to the Soviet sphere. Poland was to be partitioned in the event of its "political rearrangement"—the areas east of the Narev, Vistula, and San Rivers going to the Soviet Union, while Germany would occupy the west. Lithuania, adjacent to East Prussia, would be in the German sphere of influence, although a second secret protocol agreed in September 1939 assigned Lithuania to the USSR.
Another clause of the treaty stipulated that Bessarabia, then part of Romania, would join the Moldovan ASSR and become the Moldovan SSR under the control of Moscow. The Soviet invasion of Bukovina on 28 June 1940 violated the Molotov-Ribbentrop Pact, as it went beyond the Soviet sphere of influence as agreed with the Axis. The USSR continued to deny the existence of the Pact's protocols until after the dissolution of the Soviet Union when the Russian government fully acknowledged the existence and authenticity of the secret protocols.
End of World War II