The Great Moravian Empire around the 9th century AD.
The first Slavs arrived in present-day Slovakia in the 5th century. In the 9th century, the Great Moravian Empire stretched over Czech and Slovak lands. In 863, Christianity was brought by Byzantine brothers Saint Cyril & Methodius, from which Slovakia derived the double cross as its national symbol. From around 1000 AD, the Moravian Empire declined and Slovakia became part of the Kingdom of Hungary, separated from the Czechs where the Kingdom of Bohemia would exist for centuries. This separation would last until 1918, when Austria-Hungary disintegrated and the new state of Czechoslovakia emerged on Bohemian, Moravian, Slovakian and Ruthenian territory.
Czechoslovakia remained the only democracy in Central Europe during the interwar years. In 1938 Nazi Germany succeeded in claiming Sudetenland during the Munich Agreements, cutting Czechoslovakia into smaller pieces by establishing the Protectorate of Bohemia & Moravia in remaining Czech lands, and granting independence to the First Slovak Republic, leaving Ruthenia to Hungary.
Map of the First Slovak Republic (1938-1945). In red and blue territories ceded to Hungary in 1940. Most ethnic Hungarians in Slovakia lived in these regions and were cut out of Hungary after the Treaty of Trianon (1920), feeding Hungarian reviosionism during the Interbellum.
The First Slovak Republic was little more than a Nazi puppet state. President Josef Tiso agreed with most of Nazi policies which cost the lives of many Jews. He also agreed to cede southern parts of Slovakia to Hungary. In 1944 a coalition of various anti-fascist forces started the Slovak National Uprising against Tiso and the Nazis, but the Germans crushed the rebellion. In 1945 Soviet and Romanian troops ended Nazi rule in Slovakia and the old Czechoslovak republic was restored, except that Ruthenia was ceded to the USSR and became part of Ukraine.
Slovaks always felt the lesser compared to the Czechs. In 1969 Czechoslovakia became a federation with two constituent republics. After the Velvet Revolution of 1989 these separate governments still existed and started negotiating independence from each other. Even though the population of both countries were in slight favour of preserving unified Czechoslovakia, the Velvet Divorce happened peacefully in 1993.
Slovakia was less developed than the Czech Republic when it became independent, but succeeded in overcoming the gap during the decades after. It joined the EU in 2004 and adopted the Euro in 2009, causing an increase in foreign investment. Slovakia has become the most stable country in the region.
Currency
Slovakia never had its own currency until the First Slovak Republic replaced the Czechoslovak Koruna with its own in 1939. It was divided in 100 Halierov and at par with the Bohemian and Moravian Koruna, pegged to 10 Pfennig of the German Reichsmark. In 1940 it was devalued to 11.62 KS/RM. In 1945 this currency was replaced by a new Czechoslovak Koruna.
In 1993 newly independent Slovakia replaced the Czechoslovak Koruna with its own Koruna at par. It immediately lost around 20% versus the Czech Koruna but gradually recovered over time. Its value rose from 45 Korun/€ to 30.126 Korun/€ in 2008, the rate at which the Euro was adopted in 2009. The Czech Koruna is currently worth around 27/€.
https://en.numista.com/catalogue/slovaquie-1.html
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