Based on a house treaty, Frederick was to inherit the family's German possessions upon his father's death. After the treaty of Vienna these were no longer in the possession of the family. He instead was made heir to the Grand Duchy of Luxemburg. In 1816, Frederick relinquished this claim in exchange for land in the Netherlands and the title of Prince of the Netherlands. As a further compensation he received a yearly amount of 190,000 Dutch guilder. This made him the wealthiest member of the House of Orange-Nassau. With the money he bought a large estate in Germany, which made him the largest land owner from the Netherlands. In 1826 Frederick was appointed Commissary-general of the Department of War. In this office, Frederick reorganized the army on a Prussian model. Frederick founded the Royal military academy in Breda and reequipped the army with modern weapons. In 1829 Frederick was a for the Greek throne, but he declined because he did not want to be king of a country whose language and traditions were foreign to him. When the Belgian Revolution broke out in 1830, Frederick commanded the troops sent to Brussels to suppress the rebellion there. Frederick led these troops in several days of fighting in Brussels, but could not retake the city. Frederick also took part in his brother's 1831 Ten Days' Campaign in Belgium. When his father abdicated in 1840, Frederick withdrew from public life to his estates at Wassenaar. In 1846 he acquired Schloss Muskau in Prussia where he completed Muskau Park, the largest and one of the most famous English gardens in Central Europe, stretching along both sides of the present German–Polish border on the Lusatian Neisse. The park had been laid out from 1815 onwards at the behest of Prince Hermann von Pückler-Muskau. In July 2004, Muskau Park was added to the list of UNESCO World Heritage Sites. Upon the death of his elder brother in 1849, the country was left with a large debt. Frederick managed to pay off a million guilder to Tsar Nicholas I of Russia, who was brother-in-law to William II. The new King William III of the Netherlands did not want to inherent the kingship from his father, but Frederick managed to convince him to take up the position, offering to assist him. William III recalled Frederick and made him Inspector-General of the army. Frederick held that office until 1868, when he resigned because of the lack of support for his plans to modernize the army. Frederick managed to prevent a divorce between King William III and Queen Sophie of Württemberg by establishing a legal separation. He retired to Muskau Castle which was remodeled in Renaissance revival style between 1863 and 1866.
Marriage
Prince Frederick married in Berlin on 21 May 1825 his first cousin Louise, daughter of Frederick William III of Prussia. They had four children:
