20th-century international relations
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- What are international relations?
- What major global events took place in the 20th century?
- How did World War I impact international relations?
- What changes in international relations occurred after World War II?
- What was the Cold War and how did it shape 20th-century relations?
- How did the establishment of the United Nations influence global cooperation?
- What role did decolonization play in 20th-century international relations?
- How did the formation of organizations like NATO affect global alliances?
20th-century international relations,history of the relations between states, especially thegreat powers, from approximately 1900 to 2000.
The history of the 20th century was shaped by the changing relations of the world’s great powers. The first half of the century, the age of the World Wars and the start of theCold War, was dominated by the rivalries of those powers. The second half saw the replacement, largely through theagency of those wars, of the European state system by a world system with many centers of both power anddiscord. This article provides a singleintegrated narrative of the changingcontext of world politics, from the outbreak of World War I to the 1990s. Because domestic affairs figure heavily in theanalysis of each state’sforeign policies, the reader should consult the histories of the individual countries for more detail.
For discussion of the military strategy, tactics, and conduct of the World Wars,seeWorld War I andWorld War II.
The roots ofWorld War I, 1871–1914
Forty-three years of peace among the great powers ofEurope came to an end in 1914, when an act of political terrorism provoked two greatalliance systems into mortal combat. The South Slav campaign againstAustrian rule in Bosnia, culminating in the assassination of the Habsburgheir apparent atSarajevo, was the spark. This local crisis rapidly engulfed all the powers of Europe through the mechanisms of the Triple Alliance and theTriple Entente,diplomatic arrangements meant precisely toenhance the security of their members and to deter potential aggressors. The long-term causes of thewar can therefore be traced to the forces that impelled the formation of those alliances, increased tensions among the great powers, and made at least some European leaders desperate enough to seek their objectives even at the risk of a general war. These forces included militarism and mass mobilization, instability in domestic and international politics occasioned by rapid industrial growth, global imperialism, popularnationalism, and the rise of a social Darwinist worldview. But the question of why World War I broke out should be considered together with the questions of why peace ended and why in 1914 rather than before or after.
TheBismarckian system, 1871–90
The era of thegreat powers
The European map and world politics were less confused in the decades after 1871 than at any time before or since. The unifications of Italy and Germany removed the congeries of central European principalities that dated back to theHoly Roman Empire, while the breakup of eastern and southeastern Europe into small andquarreling states (a process that would yield the termbalkanization) was not far advanced. There the old empires, Russian, Austro-Hungarian, and Ottoman (Turkish), still prevailed. The lesser powers of Europe, including some that once had been great, like theNetherlands,Sweden, andSpain, played little or no role in the affairs of the great powers unless their own interests were directly involved. Both physical size and the economies of scale important in an industrial age rendered smaller and less developed countries impotent, while the residual habits ofdiplomacy dating from theCongress of Vienna of 1815 made the great powers the sole arbiters of European politics.
In the wider world, a diplomatic system of the European variety existed nowhere else. The outcome of theU.S.Civil War and Anglo-American settlement of the Canadian border ensured thatNorth America would not develop a multilateral balance-of-power system. South andCentral America had splintered into 17 independent republics following the final retreat of Spanish rule in 1820, but the new Latin American states were inward-looking, their centers of population and resources isolated by mountains, jungle, and sheer distance, and disputes among them were of mostly local interest. TheMonroe Doctrine,promulgated by theUnited States and enforced by theBritish navy,sufficed to spareLatin America new European adventures, the only major exception—Napoleon III’sgambit inMexico—occurring while the United States was preoccupied with civil war. When the United States purchasedAlaska from the Russiantsar andCanada acquireddominion status, both in 1867, European possessions on the American mainland were reduced to three small Guianan colonies inSouth America and British Honduras (Belize).North Africa east ofAlgeria was still nominally under the aegis of the Ottoman sultan, while sub-SaharanAfrica, apart from a few European ports on the coast, was terra incognita. The British had regularized their hold on theIndian subcontinent after putting down theIndian Mutiny of 1857–58, while the Chinese and Japanese empires remained xenophobic and isolationist. Thus, the cabinets of the European great powers were at thezenith of their influence.
Europe itself, by 1871, seemed to be entering an age of political and social progress. Britain’s Second Reform Act (1867), theFrenchThird Republic (1875), the triumph ofnationalism inItaly andGermany (1871), the establishment of universal manhoodsuffrage in Germany (1867), equality for the Hungarians in the Habsburg monarchy (1867), emancipation of the serfs inRussia (1861), and the adoption offree trade by the major European states all seemed to justify faith in the peaceful evolution of Europe toward liberal institutions and prosperity.
International peace also seemed assured onceOtto von Bismarck declared the newGerman Empire a satisfied power and placed his considerable talents at the service of stability. The chancellor knew Germany to be a military match for any rival but feared the possibility of acoalition. SinceFrance would never bereconciled to her reduced status and the loss ofAlsace-Lorraine imposed by thetreaty ending theFranco-German War, Bismarck strove to keep France isolated. In 1873 he conjured up the ghost of monarchical solidarity and formed aDreikaiserbund (Three Emperors’ League) withAustria-Hungary and Russia. Such a combination was alwaysvulnerable to Austro-Russian rivalry over theEastern Question—the problem of how to organize the feuding Balkan nationalities gradually freeing themselves from the decrepitOttoman Empire.
After the Slavic provinces of Bosnia and Hercegovina rebelled against Ottoman rule in 1875 and Russia made war on the Ottoman Empire two years later, the Dreikaiserbund collapsed. Bismarck achieved a compromise at theCongress of Berlin (1878), but Austro-Russian amity was not restored. In 1879, therefore, Bismarck concluded a permanent peacetime military alliance with Austria, whereupon the tsarist government, to court German favor, agreed to a renewal of the Dreikaiserbund in 1881. Italy, seeking aid for her Mediterranean ambitions, joined Germany and Austria-Hungary to form theTriple Alliance in 1882.
The next Balkan crisis, which erupted inBulgaria in 1885, again tempted Russia to expand its influence to the gates of Constantinople. Bismarck dared not oppose the Russians lest he push them toward an alliance with vengeful France. So instead he played midwife to an Anglo-Austro-Italian combination called theSecond Mediterranean Entente, which blocked Russian ambitions in Bulgaria while Bismarck himself concluded aReinsurance Treaty withSt. Petersburg in 1887. Once more the Eastern Question had been defused and Germany’s alliances preserved.