Bulgaria Joins the Tripartite Pact Summary

  • Last updated on November 10, 2022

After Benito Mussolini failed in his invasion of Greece, Germany made plans to invade the Balkans through Bulgaria. Bulgaria’s formal signing of the Tripartite Pact signaled its consent for German troops to traverse its territory and brought the country into the war on the Axis side.

Summary of Event

In the summer of 1940, German chancellor Adolf Hitler decided to launch an attack against the Soviet Union. The countries of the Balkans, then neutral in World War II, remained friendly to the German Third Reich, which controlled the Continent and on which they depended economically. Hitler was satisfied to allow the peninsula on his southern front to remain neutral, while England unsuccessfully tried to persuade the Balkan countries to join the Allies against Germany. Tripartite Pact (1940) World War II (1939-1945)[World War 02];Bulgarian entry World War II (1939-1945)[World War 02];Balkan campaign [kw]Bulgaria Joins the Tripartite Pact (Mar. 1, 1941) [kw]Tripartite Pact, Bulgaria Joins the (Mar. 1, 1941) [kw]Pact, Bulgaria Joins the Tripartite (Mar. 1, 1941) Tripartite Pact (1940) World War II (1939-1945)[World War 02];Bulgarian entry World War II (1939-1945)[World War 02];Balkan campaign [g]Europe;Mar. 1, 1941: Bulgaria Joins the Tripartite Pact[00150] [g]Bulgaria;Mar. 1, 1941: Bulgaria Joins the Tripartite Pact[00150] [g]Austria;Mar. 1, 1941: Bulgaria Joins the Tripartite Pact[00150] [c]Diplomacy and international relations;Mar. 1, 1941: Bulgaria Joins the Tripartite Pact[00150] [c]World War II;Mar. 1, 1941: Bulgaria Joins the Tripartite Pact[00150] [c]Wars, uprisings, and civil unrest;Mar. 1, 1941: Bulgaria Joins the Tripartite Pact[00150] Boris III Filov, Bogdan Hitler, Adolf [p]Hitler, Adolf;alliances Ribbentrop, Joachim von List, Wilhelm Mussolini, Benito

Then, in October, 1940, Italian leader Benito Mussolini ordered his armies to invade Greece from Italian-controlled Albania. When the attack failed, Hitler was forced to order an invasion of the peninsula, codenamed Operation MARITA Operation MARITA . The German forces were charged with conquering Greece, now a British ally, in order to bail out the Italian dictator.

Bulgaria’s King Boris III traveled to Berlin in November to discuss with Hitler his nation’s role in the upcoming campaign. The führer required Sofia to join the Tripartite Pact (1940)—the so-called Axis alliance among Germany, Italy, and Japan—and to allow German troops to pass through the country on their way to Greece. After the campaign was over, Bulgaria would occupy parts of Thrace and remain on guard in case Turkey joined the war on the side of Great Britain. There was no requirement for Bulgaria to participate in the Russian campaign, and in fact throughout World War II Sofia never declared war on Moscow. Later in the year, Joachim von Ribbentrop, the German foreign minister, made it quite clear to the Bulgarian ambassador in Berlin that Macedonia, Sofia’s main irredentist goal, would not be given to Bulgaria, as the Germans were also planning to have Yugoslavia join the pact and remain neutral in the Greek campaign.

Boris assured Hitler of Bulgaria’s friendship, but he was not ready to make a commitment. The Germans continued to pressure Bulgaria for the rest of the year. Finally, at the end of December, Bogdan Filov, the Bulgarian prime minister, assured the German foreign minister that Bulgaria was ready to sign the pact when the time was right. In early January, 1941, Filov traveled to Salzburg to see Ribbentrop. They agreed that Bulgaria’s military officials should meet with the German commander of the operation, Field Marshal Wilhelm List, as soon as possible to discuss details.

After the meeting between Filov and Ribbentrop at the latter’s estate in Fuschl, the two men went to Berchtesgaden to meet Hitler. Filov expressed concern over the Soviet reaction if Bulgaria joined the pact. Hitler reassured him that the Soviets would not be a concern. On the other hand, he said, without German protection, Bulgaria could easily be swallowed up by Moscow, as the Baltic states had been. Hitler’s reassurance did not persuade Filov, who was also concerned with Turkey and Yugoslavia, especially if the latter acquired Thessaloniki. He told Hitler, however, that Sofia would join the pact when it was ready.

When Turkey sent diplomatic messages suggesting it would not impede Bulgaria from joining the pact, Filov became more agreeable to Berlin’s overtures. Military talks began. When Berlin accepted Sofia’s demands for concessions, Filov agreed to join the pact on January 23, but the official signing was coordinated with the German entry into the country. In February, German technicians arrived in Bulgaria to prepare the way for the Wehrmacht’s march through the nation to Greece. British ambassador George Rendel Rendel, George raised a protest, and after a private meeting with the king, he left the country along with the ambassadors of several German-occupied Western European nations who represented their governments-in-exile in London.

Germany had planned to accomplish the passage through Bulgaria in three stages. Stage one was expected to be completed by January 26 and the final stage on February 28, but the winter weather more than the diplomatic impasse prevented implementing these plans. New plans delayed stage one until February 16 and stage three until March 28. Further complications regarding transportation delayed the timetable even further. Bulgaria also raised new objections because of the minimal support that Germany was willing to provide to protect Bulgaria from a British or Turkish attack. Filov insisted that Bulgaria’s signing of the pact coincide with the Germans entering the country. On February 28, bridges across the Danube River—marking Bulgaria’s border—were in place at three points, and the German army was ready to cross.

On March 1, 1941, Filov traveled to Vienna officially to sign the Tripartite Pact. He considered having Sofia declared an open city, but the Germans vetoed that suggestion. There was nervousness on the Bulgarian side about the Soviet Union, which at the time was still allied to Germany, but Ribbentrop assured the prime minister that the Soviets would not react. Since joining the pact was a judicial act, he said, it would not violate any military agreements. Ribbentrop also reassured Fivol that there would be no Turkish hostilities: Hitler had personally telegrammed President Ismet Inönü Inönü, Ismet to ensure his continued respect of Bulgarian territory. In any case, the German foreign minister promised, Berlin would not ask Sofia to carry out any military engagements to which the Bulgarians did not agree.

The Bulgarian parliament greeted the signing of the pact with cheers, as the national anthem was played. Only the small opposition (20 representatives out of 160, the largest group being nine Communists) refused to join in the applause. Also on March 1, the first antiaircraft units began to enter Bulgaria. The bulk of List’s Twelfth Army began its entry into the country on March 2, and, with a few setbacks, accomplished the operation according to plan.


Bulgaria’s decision to join the Axis and allow German troops into its territory brought the Balkans completely into the war. The nation did not fully join in the war effort until November 25, however, when it signed a treaty of alliance with the Axis Powers. Yugoslavia agreed to sign the Tripartite Pact as well, but the day after its representatives did so (March 25, 1941), a military coup d’état Revolutions and coups;Yugoslavia Yugoslavian revolution of 1941 overthrew the government, to the delight of much of the populace. Hitler interpreted this coup as an insult, even though the new rulers said they would not impede the Germans’ Greek campaign, and on April 6, Germany invaded both Greece and Yugoslavia. Both nations were rapidly conquered. Bulgaria was then allowed to occupy Macedonia and a small portion of western Serbia in addition to Thrace.

The German invasion of the Soviet Union World War II (1939-1945)[World War 02];Russian campaign took place in June, rather than the scheduled April. Most historians agree that this delay was critical in preventing the German army from defeating the Soviet Union. In December, Bulgaria declared war on the United States, which had entered the war that month. As a consequence, English and American bombing severely damaged Sofia. At war’s end, the victors forced Bulgaria to return the territories it had occupied, allowing it to keep only the region of Dobruja, which in 1913 it had ceded to Romania, another German ally, and received back in 1940. The Allies also placed the country in the Soviet sphere of influence, where it fell under Communist rule for forty-seven years. Tripartite Pact (1940) World War II (1939-1945)[World War 02];Bulgarian entry World War II (1939-1945)[World War 02];Balkan campaign

Further Reading
  • citation-type="booksimple"

    xlink:type="simple">Crampton, R. J. A Concise History of Bulgaria. New York: Cambridge University Press, 2005. A history of Bulgaria, including World War II, by a world-renowned history.
  • citation-type="booksimple"

    xlink:type="simple">Filov, Bogdan. “Diary.” Translated and edited by Frederick B. Chary. Southeastern Europe 1, no. 1 (1974): 70-83. The prime minister’s personal, firsthand account of the relations between Bulgaria and the Germans during World War II.
  • citation-type="booksimple"

    xlink:type="simple">Fowler, Will. Blitzkrieg 4: The Balkans and North Africa, 1941-1942. Hersham, Surrey, England: Ian Allan, 2002. A military history by a prolific author of the Balkan campaign with pictures and line drawings.
  • citation-type="booksimple"

    xlink:type="simple">Miller, Marshall. Bulgaria During the Second World War. Stanford, Calif.: Stanford University Press, 1975. A definitive study of Bulgaria during World War II.
  • citation-type="booksimple"

    xlink:type="simple">Van Creveld, Martin. Hitler Strategy, 1940-1941: The Balkan Clue. London: Cambridge University Press, 1973. An excellent scholarly monograph covering the diplomatic and military aspects of the Balkan campaign.

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Categories: History