The history of Germany and its rulers is somewhat more difficult to understand during the 18th century because, at this time, Germany was not a unified country, during the first half of the century. It would not be until Bismarck, that Germany would be unified.
Germany was, in some respects, more of a geographical expression because it was divided into three hundred states, large, small, and minute.
The peace of Westphalia in 1648 had enhanced the sovereign rights of particular German states and reduced virtually to zero the authority of their nominal overlord, the Holy Roman Emperor.
Unlike Italy, however, Germany did include two considerable powers: one long established in the family of great powers, Austria, and the relative newcomer, Prussia.
Austria enjoyed the appearances more than the realities of its great power status, while Prussia possessed few of the appearances but a great many of the realities. Thus, it is no surprise that it was the Prussian House of Hohenzollern that unified Germany and made it a power to be reckoned with.
Now take a look at the Rulers of Germany and some sites that cover their life and accomplishments. You will notice that all of the rulers are named Frederick.
Germany's Rulers and Heads of Government
800-1806 Holy Roman Empire
The Holy Roman Empire was neither holy, Roman, nor an Empire. Thus, says Voltaire. Germany was a part of this Empire, though the emperors had no real power, especially after the pragmatic sanction.
After the Treaty of Westphalia (1648), the Holy Roman Empire was little more than a loose confederation of about 300 independent principalities and 1,500 or more semi-sovereign bodies or individuals.
House of Hohenzollern
Frederick I King of Prussia (1701-13)
He succeeded to the electorate of Brandenburg in 1688 (as Frederick III), and was made the first King of Prussia for his loyalty to Emperor Leopold against the French.
Frederick William I King of Prussia (1713-40)
He fostered the internal development of Prussia in several ways. He instituted a system of rigid and efficient economy and transferred public financial administration from local governments to the central royal authority.
Frederick II, the Great King of Prussia (1740-86)
In 1772, he shared in the first partition of Poland. Under him, Prussia became a leading European power. When he died, he had doubled the area of his country, and given it a strong economic foundation.
Frederick William II King of Prussia (1786-97)
As a result of Frederick's participation in the wars of the French Revolution, he was forced in 1795 to cede to France's Prussian territories west of the Rhine River.
Frederick William III King of Prussia (1797-1840)
This king reigned during Napoleon's conquest of Europe. He sanctioned the reforms of Hardenburg and Stein, and the military reorganization of Scharnhorst and Gneisenau, sharing in the decisive victory of Leipzig with Alexander I (1813).
Confederation of the Rhine (1806-15)
Holy Roman Empire abolished -- minor German states organized as the Rheinbund [Confederation of the Rhine] with Napoleon as "Protector."