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Eastern Bloc



In the closing months of World War II and the latter half of the 1940s, the Soviet Union oversaw the establishment of Communist regimes throughout central and Eastern Europe. Over the next four decades, those regimes constituted what was informally known as the Eastern bloc. Initially, China, which fell under Communist rule in 1949, was also part of the bloc. The first major breach in the Eastern bloc occurred in 1948, when Yugoslavia was expelled amid a deepening rift with the Soviet Union. A more serious breach occurred at the end of the 1950s, when a bitter dispute erupted between China and the Soviet Union and soon became irreconcilable. The Sino-Soviet rift also inspired Albania to leave the bloc. Aside from these three breaches, however, the Eastern bloc remained intact until 1989, when the collapse of communism in Eastern Europe put an end to the bloc once and for all.


The establishment of communism in Eastern Europe proceeded at varying rates. In Yugoslavia and Albania, the indigenous Communist parties led by Josip Broz Tito (1892–1980) and Enver Hoxha (1908–1985) had obtained sufficient political leverage and military strength through their roles in the anti-Nazi resistance to eliminate their opposition and assume outright power as World War II drew to a close. In the Soviet zone of Germany, the Soviet occupation forces and control commission enabled the Socialist Unity Party of Germany (Sozialistische Einheitspartei Deutschlands, or SED) to gain preeminent power well before the East German state was formed in 1949. Similarly, in Bulgaria and Romania, Communist-dominated governments were imposed under Soviet pressure in early 1945.

Elsewhere in the region, events followed a more gradual pattern. Exiles returning from Moscow played a crucial role in the formation of what initially were broad coalition governments, which carried out extensive land redistribution and other long-overdue economic and political reforms. The reform process, however, was kept under tight Communist control, and the top jobs in the ministry of internal affairs were reserved exclusively for Communist Party members. From those posts, they could oversee the purging of the local police forces, the execution of "collaborators," the control and censorship of the media, and the ouster and intimidation of noncommunist ministers and legislators. Supported by the tanks and troops of the Soviet Army, the Communist parties gradually solidified their hold through the determined use of what the Hungarian Communist Party leader Mátyás Rákosi (1892–1971) called "salami tactics." Moscow's supervision over the communization of the region was further strengthened in September 1947 by the establishment of the Communist Information Bureau (Cominform), a body responsible for binding together the Eastern European Communist parties (as well as the French and Italian Communist parties) under the leadership of the CPSU (Communist Party of the Soviet Union). By the spring of 1948 "People's Democracies" were in place all over east-central Europe. Although the Soviet Union withdrew its support for the Communist insurgency in Greece and refrained from trying to establish a Communist government in Finland or even a Finno-Soviet military alliance, Soviet power throughout the central and southern heartlands of the region was now firmly entrenched.

Within a few weeks, however, at the June 1948 Cominform summit, the first—and in Eastern Europe the largest—crack in the Eastern bloc surfaced. Yugoslavia, which had been one of the staunchest postwar allies of the Soviet Union, was expelled from Cominform and publicly denounced. The rift with Yugoslavia had been developing behind the scenes for several months and finally reached the breaking point in the spring of 1948.

The split with Yugoslavia revealed the limits of Soviet military, political, and economic power. The Soviet leader, Joseph Stalin (1879–1953), used economic and political coercion against Yugoslavia, but these measures proved futile when Tito turned elsewhere for trade and economic assistance, and when he liquidated the pro-Moscow faction of the Yugoslav Communist Party before it could move against him. Stalin's aides devised a multitude of covert plots to assassinate Tito, but all such plans ultimately went nowhere. The failure of these alternatives left Stalin with the unattractive option of resorting to all-out military force, an option he declined to pursue.

If Yugoslavia had not been located on the periphery of Eastern Europe with no borders adjacent to those of the Soviet Union, it is unlikely that Stalin would have shown the restraint he did. Stalin's successor, Nikita Khrushchev (1894–1971), later said he was "absolutely sure that if the Soviet Union had had a common border with Yugoslavia, Stalin would have intervened militarily." Plans for a full-scale military operation were indeed prepared, but in the end the Soviet Union was forced to accept a breach of its Eastern European sphere and the strategic loss of Yugoslavia vis-à-vis the Balkans and the Adriatic Sea. Most important of all, the split with Yugoslavia raised concern about the effects elsewhere in the region if "Titoism" were allowed to spread. To preclude further such challenges to Soviet control, Stalin instructed the Eastern European states to carry out new purges and show trials to remove any officials who might have hoped to seek greater independence. The process took a particularly violent form in Czechoslovakia, Bulgaria, and Hungary.

Despite the loss of Yugoslavia, the Eastern bloc came under no further threat during Stalin's time. From 1947 through the early 1950s, the Eastern European states embarked on crash industrialization and collectivization programs, causing vast social upheaval yet also leading to rapid short-term economic growth. Stalin was able to rely on the presence of Soviet troops, a tightly woven network of security forces, the wholesale penetration of the Eastern European governments by Soviet agents, the use of mass purges and political terror, and the unifying threat of renewed German militarism to ensure that regimes loyal to Moscow remained in power. He forged a similar relationship with Communist China, which adopted Stalinist policies under Moscow's tutelage and subordinated its preferences to those of the Soviet Union. By the early 1950s, Stalin had established a degree of control over the Communist bloc to which his successors could only aspire.


After Stalin died in March 1953, a shift began within the Eastern bloc, as the new leaders in Moscow encouraged the Eastern European governments to loosen economic controls, adopt "new courses" of economic and political reform, downgrade the role of the secret police, and put an end to mass violent terror. The severe economic pressures that had built up on workers and farmers during the relentless drive for collectivization were gradually eased, and many victims of the Stalinist purges were rehabilitated, often posthumously. The introduction of these changes spawned socioeconomic unrest that had been held in check during the Stalin era through pervasive violence and oppression. From 1953 until the late 1980s the Soviet Union had to come up with alternative means of defusing centrifugal pressures in Eastern Europe—a task that was often formidably difficult.

Within a few months of Stalin's death the Eastern bloc came under serious challenge. An uprising in Plzeň and a few other Czechoslovak cities in early June 1953 was harshly suppressed by the local authorities, but a much more intractable problem arose on 17 June in East Germany, where a full-scale rebellion erupted. Coming at a time of profound uncertainty and leadership instability in both Moscow and East Berlin, the rebellion threatened the very existence of the SED regime and, by extension, vital Soviet interests in Germany. The Soviet Army had to intervene on a massive scale to put down the rebellion. The intervention of Soviet troops was crucial both in forestalling an escalation of the violence and in averting a grave fissure within the Eastern bloc.

Despite the resolution of the June 1953 crisis, the use of Soviet military power in East Germany revealed the inherent fragility of the bloc. Over the next few years, most of the leaders in Moscow were preoccupied with the post-Stalin leadership struggle and other salient domestic issues, and they failed to appreciate the implications of changes elsewhere in the bloc. Even after a large-scale rebellion broke out in the Polish city of Poznań in June 1956, Soviet leaders did not grasp the potential for wider and more explosive unrest in Eastern Europe. Not until the events of October–November 1956 did the Soviet Union finally draw a line for the bloc. Although a severe crisis with Poland in October was ultimately resolved peacefully, Soviet troops had to intervene en masse in Hungary in early November to suppress a violent revolution and get rid of the revolutionary government under Imre Nagy (1896–1958). The Soviet invasion, which resulted in heavy bloodshed, made clear to all the member states of the Warsaw Pact (the Soviet-East European military alliance formed in May 1955) the bounds of Soviet tolerance and the limits of what could be changed in Eastern Europe. The revolution in Hungary had posed a fundamental threat to the existence of the Eastern bloc, and the Soviet Union's reassertion of military control over Hungary stemmed any further erosion of the bloc.

Important as it was for the Soviet Union to consolidate its position in 1956, the bloc did not remain intact for long. A bitter split between the Soviet Union and China, stemming from genuine policy and ideological differences as well as from a personal clash between Nikita Khrushchev and Mao Zedong (1893–1976), developed behind the scenes in the late 1950s. The dispute intensified in June 1959 when the Soviet Union abruptly terminated its secret nuclear weapons cooperation agreement with China. Khrushchev's highly publicized visit to the United States in September 1959 further antagonized the Chinese, and a last-ditch meeting between Khrushchev and Mao in Beijing a few days later failed to resolve the issues dividing the two sides. From then on, Sino-Soviet relations steadily deteriorated. Although the two countries tried several times to reconcile their differences; the split, if anything, grew even wider, leaving a permanent breach in the Eastern bloc.

Khrushchev feared that the schism in world communism would deepen if he did not seek to counter China's efforts to secure the backing of foreign Communist parties. In late 1960 and early 1961 the Albanian leader, Enver Hoxha, sparked a crisis with the Soviet Union by openly aligning his country with China, a precedent that caused alarm in Moscow. The "loss" of Albania, though trivial compared to the earlier split with Yugoslavia, marked the second time since 1945 that the Soviet sphere in Eastern Europe had been breached. When Soviet leaders learned that China was secretly trying to induce other Eastern European countries to follow Albania's lead, they made strenuous efforts to undercut Beijing's attempts. As a result, no further defections from the Eastern bloc occurred by the time Khrushchev was removed from power in October 1964.


Khrushchev's successor, Leonid Brezhnev (1906–1982), had to overcome several challenges to the integrity of the bloc. The first of these was presented by Romania, which in the mid-1960s began to embrace foreign and domestic policies that were at times sharply at odds with the Soviet Union's own policies. Romania staked out a conspicuously neutral position in the Sino-Soviet dispute, refusing to endorse Moscow's polemics or to join in other steps aimed at isolating Beijing. In 1967 Romania became the first Eastern European country to establish diplomatic ties with West Germany, a step that infuriated the East German authorities. That same year, the Romanians maintained full diplomatic relations with Israel after the other Warsaw Pact countries had broken off all ties with the Israelis in the wake of the June 1967 Arab-Israeli War. Romania also adopted an independent military doctrine of "Total People's War for the Defense of the Homeland" and a national military command structure separate from that of the Warsaw Pact. Although Romania had never been a crucial member of the Warsaw Pact, the country's growing recalcitrance on foreign policy and military affairs posed serious complications for the cohesion of the alliance.

The deepening rift with Romania provided the backdrop for a much more serious challenge that arose in 1968 with Czechoslovakia and what became widely known as the Prague Spring. The introduction of sweeping political reforms in Czechoslovakia after Alexander Dubček (1921–1992) came to power in early 1968 provoked alarm in Moscow about the integrity of the Eastern bloc. Both the internal and the external repercussions of the far-reaching liberalization in Czechoslovakia were regarded by Soviet leaders as fundamental threats to the cohesion of the Warsaw Pact, especially if the developments in Czechoslovakia "infected" other countries in Eastern Europe. Soviet efforts to compel Dubček to change course were of little efficacy, as all manner of troop movements, thinly veiled threats, and political and economic coercion failed to bring an end to the Prague Spring. Finally, on the evening of 20 August 1968, the Soviet Union and four other Warsaw Pact countries—East Germany, Poland, Bulgaria, and Hungary—sent a large invading force into Czechoslovakia to crush the reform movement and restore orthodox Communist rule. Although it took several months before the last remnants of the Prague Spring could be eradicated, the final ouster of Dubček in April 1969 symbolized the forceful restoration of conformity to the Eastern bloc.

For more than a decade thereafter, the bloc seemed relatively stable, despite crises in Poland in 1970 and 1976. But the facade of stability came to an abrupt end in mid-1980 when a severe and prolonged crisis began in Poland, a crisis that soon posed enormous complications for the integrity of the bloc. The formation of Solidarity, an independent and popularly based trade union that soon rivaled the Polish Communist Party for political power, threatened to undermine Poland's role in the bloc. Soviet leaders reacted with unremitting hostility toward Solidarity and repeatedly urged Polish leaders to impose martial law, a step that was finally taken in December 1981.

The Soviet Union's emphasis on an "internal solution" to the Polish crisis was by no means a departure from its responses to previous crises in the Eastern bloc. In both Hungary and Poland in 1956, and in Czechoslovakia in 1968, Soviet leaders had applied pressure short of direct military intervention and sought to work out an internal solution that would preclude the need for an invasion. In each case Soviet officials viewed military action as a last-ditch option to be used only if all other alternatives failed. An internal solution proved feasible in Poland in 1956, but attempts to reassert Soviet control from within proved futile in Hungary in 1956 and Czechoslovakia in 1968. During the 1980–1981 Polish crisis Soviet officials devised plans for a full-scale invasion, but these plans were to be implemented only if the Polish authorities failed to restore order on their own. Only in a worst-case scenario, in which the martial-law operation collapsed and civil war erupted in Poland, does it seem at all likely that the Soviet Union would have shifted toward an "external" option.

The successful imposition of martial law in Poland by General Wojciech Jaruzelski (b. 1923) in December 1981 upheld the integrity of the Eastern bloc at relatively low cost and ensured that Soviet leaders did not have to face the dilemma of invading Poland. The surprisingly smooth implementation of martial law in Poland also helped prevent any further disruption in the bloc during the final year of Brezhnev's rule and the next twoand-a-half years under Yuri Andropov (1914–1984) and Konstantin Chernenko (1911–1985). During an earlier period of uncertainty and leadership transition in the Soviet Union and Eastern Europe (1953–1956), numerous crises had arisen within the bloc; but no such upheavals occurred in 1982–1985. This unusual placidity cannot be attributed to any single factor, but the martial-law crackdown of December 1981 and the invasions of 1956 and 1968 probably constitute a large part of the explanation. After Stalin's death in 1953, the limits of what could be changed in Eastern Europe were still unknown, but by the early to mid-1980s the Soviet Union had evinced its willingness to use "extreme measures" to prevent "deviations from socialism." Thus, by the time Mikhail Gorbachev (b. 1931) assumed the top post in Moscow in March 1985, the Eastern bloc seemed destined to remain within the narrow bounds of orthodox communism as interpreted in Moscow.


Although Gorbachev initially carried out few changes in the Eastern bloc, he began shifting course within a few years of taking office, as he steadily loosened Soviet ties with Eastern Europe. The wide-ranging political reforms he was promoting in the Soviet Union generated pressure within Eastern Europe for the adoption of similar reforms. Faced with the prospect of acute social discontent, the Hungarian and Polish governments embarked on sweeping reform programs that were at least as ambitious as what Gorbachev was pursuing. By early 1989 it had become clear that the Soviet Union was willing to countenance radical changes in Eastern Europe that cumulatively amounted to a repudiation of orthodox communism.

In adopting this approach, Gorbachev did not intend to precipitate the breakup of the Eastern bloc. On the contrary, he was hoping to strengthen the bloc and reshape it in a way that would no longer require heavy-handed coercion. But in the end his policies, far from invigorating the bloc, resulted in its demise. In early June 1989 elections were held in Poland that led within three months to the emergence of a noncommunist government led by Solidarity. Political changes of similar magnitude were under way at this time in Hungary. Although the four other Warsaw Pact countries—East Germany, Bulgaria, Czechoslovakia, and Romania—tried to fend off the pressures for sweeping change, their resistance proved futile in the final few months of 1989, when they were engulfed by political turmoil. The orthodox Communist rulers in these four countries were forced from power, and noncommunist governments took over. In 1990 free elections were held in all the Eastern European countries, consolidating the newly democratic political systems that took shape after the Communist regimes collapsed.

By that point, events had moved so far and so fast in Eastern Europe, and the Soviet Union's influence had declined so precipitously, that the fate of the whole continent eluded Soviet control. The very notion of an "Eastern bloc" lost its meaning once Gorbachev permitted and even facilitated the end of Communist rule in Eastern Europe. This outcome may seem inevitable in retrospect, but it was definitely not so at the time. If Gorbachev had been determined to preserve the Eastern bloc in its traditional form, as his predecessors had been, he undoubtedly could have succeeded. The Soviet Union in the late 1980s still had more than enough military strength to prop up the Communist regimes in Eastern Europe and to cope with the bloodshed that would have resulted. Gorbachev's acceptance of the peaceful disintegration of the bloc stemmed from a conscious choice on his part, a choice bound up with his domestic priorities and his desire to do away with the legacies of the Stalinist era that had blighted the Soviet economy. Any Soviet leader who was truly intent on overcoming Stalinism at home had to be willing to implement drastic changes in relations with Eastern Europe. Far-reaching political liberalization and greater openness within the Soviet Union would have been incompatible with, and eventually undermined by, a policy in Eastern Europe that required military intervention on behalf of hard-line Communist regimes. The fundamental reorientation of Soviet domestic goals under Gorbachev therefore necessitated the adoption of a radically new policy vis-à-vis Eastern Europe that led, in short order, to the dissolution of the Eastern bloc.

See alsoBerlin Wall; 1989; Prague Spring; Solidarity; Soviet Union; Warsaw Pact.


Brzezinski, Zbigniew K. The Soviet Bloc: Unity and Conflict. Cambridge, Mass., 1967.

Gati, Charles. The Bloc That Failed: Soviet–East European Relations in Transition. Bloomington, Ind., 1990.

Hutchings, Robert L. Soviet–East European Relations: Consolidation and Conflict, 1968–1980. Madison, Wis., 1983.

Kramer, Mark. "The Soviet Union and Eastern Europe: Spheres of Influence." In Explaining International Relations since 1945, edited by Ngaire Woods. Oxford, U.K., 1996.

Smith, Alan H. The Planned Economies of Eastern Europe. London, 1983.

Mark Kramer

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