The two postcards my Bulgarian great-grandfather wrote so many decades ago were stored in a box between documents, military medals and decorations, wrapped in crumpled transparent foil. One is dated April 1945, with a school in Pecs, Hungary on the front. "I am in good health. And I hope that you are also in good health at home," Hristo Ivanov, pressed into military service by the Red Army because he was a veterinarian, wrote to his daughter.

The second card is dated May 17, 1945, and shows an idyllic street promenade in Deutschlandsberg, Austria. Hristo Ivanov wrote to the family that he might be coming home soon: "Study and be diligent, so when the war is over and I come home, you can welcome me proudly," he admonished his daughter. In his opinion, you would always succeed with diligence and learning.

He was to be proven wrong.

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The Soviets — liberators or occupying force?

The Red Army invaded Bulgaria in September 1944. Up to 30,000 people were killed over the next three months — former ministers, journalists, clergymen, businessmen, intellectuals and large landowners, all accused of shunning the Communist system. Thousands of people were killed at the Belene concentration camp on the island of the same name.

It turned out that diligence and learning made no difference; people needed to be affiliated to the right party.

As my grandmother was not a card-carrying member of the Communist party, she was not allowed to go to medical school. Instead, she became a teacher of biology and chemistry in a small village. My great-grandfather's brother allegedly committed suicide, but nobody in the family believes that — they say he was killed. He was openly skeptical about the establishment of Communist rule in Bulgaria.

That sentiment continues to divide public opinion to this day. Some feel the Red Army liberated Bulgaria in September 1944, others say the country was occupied.

Caught between two fronts

Bulgaria did not take part in the war until 1941, when, at the insistence of Tsar Boris III, the country joined the Tripartite Pact. German troops were stationed in the country. The rulers in Sofia hoped this alliance with Germany would garner them occupation zones in the countries to the immediate west, parts of what is today Serbia and Northern Macedonia.

Three years later, the Red Army stood at Bulgaria's borders. On September 5, 1944, the Soviet Union declared war on the Tsardom of Bulgaria, rejecting an armistice demanded by the Bulgarian side. The Red Army marched across the northern border and occupied the Black Sea resort towns Varna and Burgas, capturing the German sailors that had stayed behind. Bulgaria broke off diplomatic relations with Germany that same day.

When the Red Army invaded Bulgaria, they hardly encountered any resistance. Many people were dissatisfied with the government and the monarchy. Without further ado, a Moscow-controlled puppet government was established. Now Bulgaria was on the Soviet side, and Germany the enemy. Many men were drafted by the Red Army, including my great-grandfather.

When WWII ended, Bulgaria was on the side of the victorious powers. "Bulgaria needs friendship with the USSR like every living being needs air and sunshine," the future communist Prime Minister, Georgi Dimitroff, described the new alliance. Many people even today say Bulgaria was liberated, even if the Soviet influence after the end of the war did not bring the longed-for freedom.

The presence of the past

After the fall of the Berlin Wall and the collapse of the Communist regime, many Eastern European states began to try to come to terms with the past — but not Bulgaria. Even 30 years after the fall of the Berlin Wall and the transition to democracy, there is little public debate about the atrocities committed by the Communist regime. The 10th grade history textbooks were finally rewritten last year, according to a law from the year 2000 that described the communist regime as criminal.

Western-oriented civil society has demanded the removal of Russian monuments for years. Activists regularly spray them with bright colors and transform the Red Army soldiers into heroes of Western pop culture like Superman or Captain America.

After the Crimean annexation, a monument in Sofia wore Ukraine's national colors. Activists later decorated that same monument with a crocheted balaclava made popular by the Russian protest band Pussy Riot. More than 75 years after the end of the Second World War, these monuments are a symbol of the fragmentation of Bulgarian society — a society that has not yet found a way to approach its own history.

May 9 is a day that disunites

While on May 9, most European countries celebrate the 1950 Schuman Declaration — basically the founding of the European Union — Russia and other former USSR satellites states hold military parades to celebrate the victory over Nazi Germany on that day. Bulgaria, poised between East and West, between Russian nostalgia and Western orientation, is torn between the two, and every year, the rifts grow deeper.

Bulgaria commemorates both occasions, but the celebrations of the victory over Nazi Germany have a much larger dimension: thousands of people gather every year in downtown Sofia, festive with Bulgarian and Russian flags. People sing Russian songs, schoolchildren wear yellow-and-black-striped St George's ribbons, a Soviet symbol of military bravery in the Second World War, and wreaths are laid.

All of this takes place beneath the great monument to the Red Army: 40 meters tall, with the statue of a Red Army soldier pointing a gun at the sky. In 1993, the city council decided to demolish the monument. So far, no one has dared to enforce the decision.

An old man's hopes

My great-grandfather experienced the independence of Bulgaria in 1908, the monarchy, the invasion of the Red Army in 1944 and the following 45 years of communist rule. He even witnessed the early years of democracy. He had great hopes for Bulgaria's future. He died in 1991, at the age of almost 90. I remember an old man who liked to sit in a chair facing the sea. He never talked to me about the war, only about how the Black Sea froze so thoroughly in the 1950s that he could walk on the ice.

Bulgaria has been a member of NATO since 2004, and a member of the EU since 2007. Its orientation towards the West has not cooled its ties to Russia, neither emotionally nor economically. After 1989, the monopoly of power of the Bulgarian Communist Party was dissolved, but the power did not change hands from the elite. Bulgaria still has a long way to go in coming to terms with its own past.