In what year was Royal Prussia annexed?
In the 1772 First Partition of Poland, the Prussian king Frederick the Great annexed neighboring Royal Prussia, i.e. the Polish voivodeships of Pomerania (Gdańsk Pomerania or Pomerelia), Malbork, Chełmno and the Prince-Bishopric of Warmia, thereby bridging the "Polish Corridor" between his Prussian and Farther Pomeranian lands and cutting remaining Poland off the Baltic Coast.