The Saxons (Germans mostly from Saxony Region) came to these lands in the 13th century (700 years ago!) after the Mongol Invasions that devastated this part of Medieval Europe.
They maintained their culture, language and customs. They even had their own party in the first Czechoslovak Republic (1919-1938). In some areas, towns, villages they were a majority, especially here in Zips (Spiš). The end of the WW2, Stalin’s “nations engineering” and president Beneš decrees forced them to leave the land of their ancestors and flee to Germany - which wasn’t really their homeland anymore.
From some 128.000 Germans in whole Slovakia before WW2 only 20.000 still lived there in 1947. Nowadays, the official number is even much lower - 6100 according to the last census. In Spiš Region, there is only one village that is said to be still purely Zipser-German (Spiš-German) - Chmeľnica, with some 900 habitants. Its population avoided being expelled just because they had been warned about the coming deportation troops and escaped to the the forest. After the war, they all declared a Slovak nationality to avoid being deported.