Frederick William II was King of Prussia and Elector of Brandenburg for 11 years in the late 18th Century.

He was born on Sept. 25, 1744, in Stadtschloss, Berlin. His father was Prince Augustus William of Prussia, and his mother was Duchess Luise of Brunswick-Wolfenbüttel. His uncle was the dynamic Prussian ruler Frederick II, who would later be known as Frederick the Great.

When Frederick William was 14, his father died. Frederick II had no children. Thus, in 1758, the boy became heir to the Prussian throne. He married in 1765, to Elisabeth Christine of Brunswick-Wolfenbüttel. They divorced four years later, having had one child together: Frederica Charlotte (1767). In the same year in which he was divorced, Frederick William married agian, to Frederick Louisa of Hesse-Darmstadt. They had seven children, six of whom lived into adulthood: Frederick William (1770), Louis Charles (1773), Frederick Louisa Wilhelmina (1774), Augusta (1780), Henry (1781), and William (1783).

Frederick the Great died on Aug. 17, 1786. From that point, his successor became King Frederick William II.

The new ruler was very much the antithesis of his predecessor. Frederick the Great had made Prussia into a world power on the back of a strong military and a handful of stunning military victories. The state was growing and advancing, in technology and prestige. The new ruler had not much care for military matters; under this negligence from on high, the training and morale of the army deteriorated.

When the French Revolution began, in 1789, Frederick William was as alarmed as other European monarchs at the possible fate of the French king, Louis XVI. The Prussian king met with Holy Roman Emperor Leopold II in August 1791; the result was the Declaration of Pillnitz, which declared Prussian and Russian support for Louis XVI and urged other European monarchs to join in an effort to return him to his throne.

The French Revolutionary Wars began in 1792. Prussian was a main antagonist. French troops were initially very successful, winning at Valmy and then taking Mainz and Frankfurt. The king was involved in the campaigns of the first two years of the war. A sharp decrease in available funds, couples with the deterioration in quality of troops in the field, led to a dramatic Prussian reverse. Frederick William entered into a treaty with Great Britain and the Netherlands in 1794, but it still wasn't enough to stave off defeat. The 1795 Treaty of Basel ended Prussia's involvement in the struggle against France–for a time. A chagrined Prussia set about recovering, while the war still raged arounds its borders. Prussia had played a part in two more Partitions of Poland but had gained little in real terms from either.

Frederick William II died on Nov. 16, 1797, in Potsdam. His oldest son became King Frederick William III.