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Around 874 AD the Vistulans are subjugated by the Great Moravian King Svatopluk I who incorporates their territory to the First West Slavic Kingdom in the region. (Present day border of Czech Republic & Slovakia).
The coming of the Magyars in 900 AD ended the existence of the short-lived kingdom, making way for the Bohemian Duke Boleslaus I in (955 AD) who was assigned with the control of the area by Otto I, Holy Roman Emperor, after their common victory over the invading nomads.