As a soldier he received the usual training of a Prussian prince, obtained his lieutenancy in 1784, became a colonel in 1790, and took part in the campaigns against France of 1792-1794. On December 24, 1793, Frederick William married Louise of Mecklenburg-Strelitz. They had ten children. In the "Kronprinzenpalais" (Crown Prince's palace) in Berlin, Frederick William lived a civil life with a problem-free marriage, which did not change even when he became King of Prussia in 1797.