Saint Adalbert of Prague.
breski1 Adalbert of Prague (Latin: Adalbertus; c. 956 – 23 April 997), known in Czech by his birth name Vojtěch (Latin: Voitecus), was a Bohemian missionary and Christian saint. He was the Bishop of Prague and a missionary to the Hungarians, Poles, and Prussians, who was martyred in his efforts to convert the Baltic Prussians to Christianity. He was said to be the composer of Bogurodzica, the oldest known Polish hymn, but this is now thought unlikely, as he did not know the language.en.wikipedia.org/wiki/Adalbert_of_Prague St. Adalbert (or St. Vojtěch; Czech: Svatý Vojtěch , Polish: Święty Wojciech) was later declared the patron saint of Bohemia, Poland, Hungary and the former polity of Prussia.