Dukes of Prussia
1525-1568 Albert I
1568-1618 Albert II Frederick
1618-1619 John Sigismund
1619-1640 George William
1640-1688 Frederick William
1688-1701 Friedrich I * – became first King in Prussia in 1701

Kings of Prussia (known as Kings In Prussia until 1772)
1701-1713 Friedrich I
1713-1740 Friedrich Wilhelm I
1740-1786 Friedrich II (Frederick The Great)
1786-1797 Friedrich Wilhelm II
1797-1840 Friedrich Wilhelm III
1840-1861 Friedrich Wilhelm IV
1861-1888 Wilhelm I * – became first German Emperor (Kaiser) in 1871

German Emperors and Kings of Prussia
1871-1888 Wilhelm I
1888-1888 Friedrich III
1888-1918 Wilhelm II * – abdicated as the last German Emperor and King of Prussia

Pretenders to the Throne
1918-1941 Wilhelm II
1941-1951 Crown Prince Wilhelm
1951-1994 Prince Louis Ferdinand
1994-present Prince Georg Friedrich