Johann Sebastian Bach was a German composer and musician of the late Baroque period. He is known for his orchestral music such as the Brandenburg Concertos; instrumental compositions such as the Cello Suites; keyboard works such as the Goldberg Variations and The Well-Tempered Clavier; organ works such as the Schubler Chorales and the Toccata and Fugue in D minor; and vocal music such as the St Matthew Passion and the Mass in B minor. Bach is widely regarded as one of the greatest and most influential composers in the history of Western music.
Johann von Posilge was a parish priest of Deutsch Eylau (Iława) and later assistant to Bishop of Pomesania. He is better known as the author of Chronik des Landes Preussen, a chronicle detailing events in Prussia from around 1360. It is one of the most important sources on the history of the Teutonic Knights for the period. After his death, the chronicle was translated from Latin to German continued to 1420. Posilge was not a German, but a native Prussian, born in the village of Posilge, east of Marienburg (Malbork). As such, he was more critical of the Knights and deviated from traditional overly panegyric chronicles of the time.