Slovakia, formally the Slovak Republic, is a landlocked nation in Central Europe that borders the Czech Republic and Hungary. Its northern and eastern borders are shared with Poland, while its southern and western borders are shared with Hungary, Austria, and the Czech Republic. Its northern and western borders are shared with Poland, Ukraine, and the Czech Republic. Slovakia's mainly hilly terrain covers about 49,000 square kilometres (19,000 square miles), and the country has a population of more than 5.4 million people. Bratislava is the country's capital and biggest city, while Kosice is the country's second largest city.
In the 5th and 6th centuries, the Slavs made their way into the area that is now known as Slovakia. It was during the 7th century that they played a pivotal part in the establishment of Samo's Empire. They founded the Principality of Nitra in the 9th century, which was subsequently overrun by the Principality of Moravia, which resulted in the establishment of Great Moravia. Following the collapse of Great Moravia in the 10th century, the area was absorbed by the Principality of Hungary, which would later become the Kingdom of Hungary in 1000. Following the Mongol invasion of Europe in 1241 and 1242, a large portion of the country was devastated. The territory was fully reclaimed due to King Béla IV of Hungary, who also brought German settlers to the area, enabling them to establish themselves as a significant ethnic group in the region, particularly in what are now portions of central and eastern Slovakia.