Friedrich von Pernstein

Friedrich von Pernstein (c. 1270–1340), a Moravian nobleman and Franciscan, was Archbishop of Riga from 1304. His episcopate was consumed by war with the Teutonic Order, which built Dünamünde castle to blockade the city.

He negotiated with Grand Duke Gediminas of Lithuania over conversion, helping to bring the Order's expulsion from Lithuania, and Riga's citizens backed him against the knights.

In 1330 the Order laid the foundations of Riga Castle and took control. Of his 37 years as archbishop, Friedrich spent fewer than five in Riga, living mostly at the papal court in Avignon, where he amassed a library and died in 1340.