Columbia subject headings:
Diplomatic and consular service--Prussia (Duchy)
Prussia (Duchy)--Diplomatic and consular service.
Prussia (Duchy)--Foreign relations.
Sigismund I, King of Poland, 1467-1548.
Harvard subject headings:
Albert, Duke of Prussia, 1490-1568.
Diplomatic and consular service--Prussia (Duchy)
Poland--Foreign relations--Prussia (Duchy)
Prussia (Duchy)--Foreign relations--Poland.
Sigismund I, King of Poland, 1467-1548.
Princeton subject headings: