In the aftermath of World War I, Romania, which fought with the Entente against the Central Powers, had greatly expanded its territory, incorporating the regions of Transylvania, Bessarabia and Bukovina, largely as a result of the vacuum created by the collapse of the Austro-Hungarian and Russian empires. This led to the achievement of the long-standing nationalist goal of creating a Greater Romania,
a national state that would incorporate all ethnic Romanians.
However, the newly gained territories also included significant Hungarian, German, Bulgarian, Ukrainian and Russian minorities, which put Romania at odds with several of her neighbors. This occasionally led to violent conflict, as exemplified by the Hungarian-Romanian War and the Tatarbunary uprising. To contain Hungarian irredentism, Romania, Yugoslavia and Czechoslovakia established the Little Entente in 1921. That same year, Romania and Poland concluded a defensive alliance against the emergent Soviet Union, and in 1934 the Balkan Entente was formed with Yugoslavia, Greece and Turkey, who were suspicious of Bulgaria.
Since the late 19th century, Romania had been a relatively democratic constitutional monarchy with a pro-Western outlook, but the country faced increasing turmoil in the 1930s as a result of the Great Depression and the rise of fascist and other far-right movements such as the Iron Guard , which advocated revolutionary terrorism against the state. Under the pretext of stabilizing the country, the increasingly autocratic King Carol II proclaimed a "royal dictatorship" in 1938.
The new regime featured corporatist policies that often resembled those of Fascist Italy and Nazi Germany.
In parallel with these internal developments, economic pressures and a weak Franco-British response to Hitler's aggressive foreign policy caused Romania to start drifting away from the Western Allies and closer to the Axis.
On 13 April 1939, France and the United Kingdom had pledged to guarantee the independence of the Kingdom of Romania. Negotiations with the Soviet Union concerning a similar guarantee collapsed when Romania refused to allow the Red Army to cross its frontiers.
On 23 August 1939 Germany and the Soviet Union signed the Molotov-Ribbentrop Pact. Among other things, this pact recognized the Soviet "interest" in Bessarabia (which had been ruled by the Russian Empire from 1812–1918). This Soviet interest was combined with a clear indication that there was an explicit lack of any German interest in the area.
Eight days later, Nazi Germany invaded the Second Polish Republic. Expecting military aid from Britain and France, Poland chose not to execute its alliance with Romania in order to be able to use the Romanian Bridgehead. Romania officially remained neutral and, under pressure from the Soviet Union and Germany, interned the fleeing Polish government after its members had crossed the Polish-Romanian border on 17 September, forcing them to relegate their authority to what became the Polish government-in-exile.
After the assassination of Prime Minister Armand Călinescu on 21 September King Carol II tried to maintain neutrality for several months longer, but the surrender of the Third French Republic and the retreat of British forces from continental Europe rendered the assurances that both countries had made to Romania meaningless.
Romania after the territorial losses of 1940. The recovery of Bessarabia, roughly corresponding to the Moldavian Soviet Socialist Republic , was the catalyst for Romania's entry into the war on Germany's side.
In 1940, Romania's territorial gains made following World War I were largely undone. In July, after a Soviet ultimatum, Romania agreed to give up Bessarabia and Northern Bukovina. Two thirds of Bessarabia were combined with a small part of the Soviet Union to form the Moldavian Soviet Socialist Republic.
The rest (Northern Bukovina, northern half of the Hotin county and Budjak ) was apportioned to the Ukrainian Soviet Socialist Republic. Shortly thereafter, on 30 August, under the Second Vienna Award, Germany and Italy mediated a compromise between Romania and the Kingdom of Hungary: Hungary received a region referred to as "Northern Transylvania", while "Southern Transylvania" remained part of Romania. Hungary had lost Transylvania after World War I in the Treaty of Trianon.
Second Vienna Award
On 7 September, under the Treaty of Craiova, Southern Dobruja (which Bulgaria had lost after the Romanian invasion during the Second Balkan War in 1913), was ceded to Bulgaria under pressure from Germany. Despite the relatively recent acquisition of these territories, they were inhabited by a majority of Romanian speaking people (except Southern Dobruja), so the Romanians had seen them as historically belonging to Romania, and the fact that so much land was lost without a fight shattered the underpinnings of King Carol's power.
On 4 July Ion Gigurtu formed the first Romanian government to include an Iron Guardist minister, Horia Sima. Sima was a particularly virulent anti-Semite who had become the nominal leader of the movement after the death of Corneliu Codreanu . He was one of the few prominent far-right leaders to survive the bloody infighting and government suppression of the preceding years.
Antonescu ja Hitler
In the immediate wake of the loss of Northern Transylvania, on 4 September the Iron Guard (led by Horia Sima) and General (later Marshal) Ion Antonescu united to form a "National Legionary State" government, which forced the abdication of Carol II in favor of his 19-year-old son Michael. Carol and his mistress Magda Lupescu went into exile, and Romania, despite the unfavorable outcome of recent territorial disputes, leaned strongly toward the Axis. As part of the deal, the Iron Guard became the sole legal party in Romania. Antonescu became the Iron Guard's honorary leader, while Sima became deputy premier.
In power, the Iron Guard stiffened the already harsh anti-Semitic legislation, enacted legislation directed against minority businessmen, tempered at times by the willingness of officials to take bribes, and wreaked vengeance upon its enemies.
On 8 October German troops began crossing into Romania.
They soon numbered over 500,000.
On 23 November Romania joined the Axis powers. On 27 November, 64 former dignitaries or officials were executed by Iron Guard in Jilava prison while awaiting trial (see Jilava Massacre). Later that day, historian and former prime minister Nicolae Iorga and economist Virgil Madgearu, a former government minister, were assassinated.
The cohabitation between the Iron Guard and Antonescu was never an easy one. On 20 January 1941, the Iron Guard attempted a coup, combined with a pogrom against the Jews of Bucharest. Within four days, Antonescu had successfully suppressed the coup. The Iron Guard was forced out of the government. Sima and many other legionnaires took refuge in Germany; others were imprisoned. Antonescu abolished the National Legionary State, in its stead declaring Romania a "National and Social State.