Before the First World War, the Austro-Hungarian dual monarchy was a big multinational state and stretched from modern-day Italy to Ukraine and from Czech Republic to Croatia. Czechia had been a part of this empire since the mid-16th century and Hungarians had ruled Slovakia since the 11th century. The Germans living on the territory dominated the society but eventually granted the Slavic majority more and more representation.
An independence movement only picked up pace in 1914, when the First World War started and the Czech became afraid that Germany and Austria might unite, so that the Germans would be overly dominant in Czechia again. They started lobbying for independence and the Slovakians joined them. From 1915, the group called for a common state.
The allies liked the idea because they wanted a reliable partner in central Europe. So when Austria had lost the war, the US made it a ceasefire condition that Czechoslovakia could become independent. Austria accepted and the new state was proclaimed on 28th Oct 1918. Czechia became independent instantly, the Slovakians only after eight months when the Hungarians finally stopped fighting. Besides, a tiny part of modern-day Ukraine joined the union in 1919.
The new republic wasn’t only economically successful but also central Europe‘s only functioning democracy after 1933. Things went south when Germany annexed the regions close to its border in 1938 and Czechoslovakia’s allies in the Western world wanted to appease Germany by doing nothing. In 1939, Germany took the rest of Czechia, and Slovakia became a German puppet state.
With the end of the Second World War in 1945, Czechoslovakia regained its independence and gave its eastern most part to the Soviets – which had already made deals with the Czechoslovakian government in exile during the war. The Czechoslovakian communists were eventually voted into office in 1946 and started remodelling the country along undemocratic Soviet lines in 1948.
In the 1960s, the Czechoslovakian communists around Alexander Dubček enforced a more free and democratic socialism by allowing for freedom of press or releasing political prisoners. Since the Soviet Union wasn’t happy with that “Prague Spring”, the Warsaw Pact sent troops to end it. Unsurprisingly, the next president was very committed to Soviet ideas.
Real existing socialism collapsed in 1989 when excessive policy brutality against a student protest provoked around 750.000 people to protest against the regime in Prague. The government couldn’t possibly hush crowds like that and its leading politicians resigned without retreating to violence – hence the name “Velvet Revolution”.
The first free elections in 1990 disempowered the communists. The new government had to organise the new state and its switch from a socialist to a capitalist economy. However, Czech and Slovakian politicians couldn’t agree. Instead, they started discussing splitting up the country and Czechoslovakia was divided into two independent states in 1993. The majority of the population wasn’t in favour of the split though and kept friendly relations. Even nowadays, the local “American Idol” caters to both countries.