Prince Henry of Prussia (1726–1802)

Born in Berlin, Henry was the 13th child of King Frederick William I of Prussia and Princess Sophia Dorothea of Hanover. Henry's conflicts with his older brother, King Frederick II of Prussia, are almost legendary. Although remarkably similar in appearance and personality (both were fond of the arts and French literature, and both were exceptional military commanders) Henry resented being in Frederick's shadow. Nonetheless, he loyally served as one of his brother's top generals throughout Frederick's reign. Henry tended to be less aggressive than the King in battle; although he never won a victory of the scale of Rossbach or Leuthen (two of Frederick's greatest victories), his caution served him well as he was never defeated on the battlefield.

When he was only 14, Henry was appointed as Colonel of the 35th Infanterieregiment by Frederick after he became king in 1740, leading Henry to participate in the first two Silesian Wars. Henry lived in the shadow of his older brother and sometimes criticized the king's military strategies and foreign policies, although in later years the brothers became closer. In 1753 he published his memoirs under the pseudonym "Maréchal Gessler".

Princess Wilhemina of Hesse-Kassel

On 25 June 1752 Henry married Princess Wilhelmina of Hesse-Kassel in Charlottenburg, but they had no children. Henry lived in Rheinsberg Palace after receiving it as a gift from his brother who also had a grand palace built for him in Berlin between 1748 and 1753. Despite the marriage, he scarcely concealed his passion for other men and developed intimate friendships with the actor Blainville and the French emigre Count La Roche-Aymon. One favourite, Major von Kaphengst, exploited the prince's interest in him to lead a dissipated, wasteful life at Schloss Meseberg, an estate not far from Rheinsberg which Henry had given to him.

Henry successfully led Prussian armies as a general during the Third Silesian War (1756–1763, part of the Seven Years' War). He greatly distinguished himself during his brother's victory at the Battle of Prague and fought heroically during the Prussians' subsequent defeat at Kolin. After the Prussian Army's initial success against one wing of the joint Russian and Austrian Armies in the Battle of Kunersdorf, Henry urged his brother Frederick to stop attacking. The king, who had already sent a message of victory to Berlin, pressed the attack. The day ended with a virtually destroyed Prussian army, a virtually defenseless Kingdom of Prussia, and a complete victory by the Russo-Austrian force. Afterwards, Henry reorganized the routed Prussian forces. Frederick came to rely on his brother as commander of the Prussian forces in the east, Frederick's strategic flank. Henry later won his most famous victory at Freiberg in 1762, the final battle of the war between Austria and Prussia; Frederick wrote to him, "You alone have the honor of breaking down Austrian obstinacy."

After the Seven Years' War, Henry worked as a shrewd diplomat who helped plan the First Partition of Poland through trips to Stockholm and St. Petersburg. During the War of the Bavarian Succession he commanded one of the two Prussian main armies, but saw little action. In the 1780s he made two diplomatic trips to France. He was a friend of Jean-Louis Favier.

Henry attempted to secure a principality for himself and twice tried to become King of Poland, but was opposed by a displeased Frederick. The king frustrated Henry's attempt to become ruler of a kingdom Catherine II of Russia planned to create in Wallachia.

Prince Henry's grave in Rheinsberg Palace.

In 1786 either Nathaniel Gorham, then-President of the Continental Congress, or Friedrich Wilhelm von Steuben, the Prussian general who served in the Continental Army, suggested to Alexander Hamilton that Henry should become President or King of the United States, but the offer was revoked before the prince could make a reply.

After the death of Frederick in 1786, Henry hoped to become more influential in the Prussian government as the advisor of his nephew, the new King Frederick William II of Prussia. Although he was less influential than he hoped, Henry was more important during the last years of his life in advising King Frederick William III, who began his reign in 1797. Voltaire had seen in Frederick the embodiment of his "Philosopher King". Arguably, Henry was by deed the man Voltaire had hoped the "Age of Reason" would produce.

Prince Henry (by J. H. Tischbein, 1769)

Henry died at Rheinsberg Palace.

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  Prince Henry's Palace in Berlin (now Humboldt University)

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  Rheinsberg Palace