Solms was born posthumously, the third son and fifth child of Hermann Otto Erbprinz zu Solms-Hohensolms-Lich (1902–1940). His father was the heir to the fortune and legacy of the Princes zu Solms-Hohensolms-Lich, a noble family known in Germany since 1129, whose Imperial county was made a principality of the Holy Roman Empire in 1792, but mediatized under the sovereignty of the Grand Duchy of Hesse in 1806. Hermann Otto's father died while serving as a lieutenant in the Luftwaffe at Neuruppin on 3 July 1940. His mother, "née" Baroness Gertrude von Werthern-Beichlingen (1913–1987), was remarried in 1950 to Hans Joachim Sell of Neustettin.