Slovakia as a state did not exist before the First World War. After that war, Czechoslovakia was one of the independent states that were carved out of the former Austro-Hungarian Empire. Czechs and Slovaks, whose languages are rather similar, lived together in the same state, along with a significant minority of ethnic German who inhabited the Sudetenland.
We all know how Hitler used the issue of the Sudeten Germans to attack and eventually dismember Czechoslovakia in the late 1930s. After first annexing the Sudetenland for the Third Reich, he encouraged Jozef Tiso, a Catholic priest and the leader of the Slovak People’s Party, to declare Slovakia’s independence. Tiso declared Slovakia independent on 14th March 1939. The next day Hitler invaded what was left of Czechoslovakia, which he turned into the Nazi “protectorate” of Bohemia and Moravia.
Slovakia established its own currency, of 100 halierov to the crown, and below you can see the Slovak coat of arms as it appeared on the obverse of the coinage. Beneath that, you can see an image of President Tiso.