The differences in religious affiliation between the Czech Republic and Slovakia are almost proverbial. The Czechs are known as the most atheistic nation in Europe, while Slovakia is one of the countries with the highest religious identification in Europe, alongside countries such as Poland, Ireland and Malta, due to the number of people who subscribe to institutionalized religion, but also due to some legislative specificities (the threshold for registration of religious organizations in the Czech Republic is 300 members, in Slovakia it is 50,000, and the Slovak Republic also has a specific treaty with the Holy See).
The 18th century was crucial for the Czech Republic. In what way? You can read about it in our regular Coffee Beans.