Background
Frederick was born as the son of Count John George I of Solms (d 1600). When his father inheritance was divided in 1607, he received the districts of Rödelheim, Pletenheim and Assenheim.
Frederick was born as the son of Count John George I of Solms (d 1600). When his father inheritance was divided in 1607, he received the districts of Rödelheim, Pletenheim and Assenheim.
His part of the County of Solms was named Solms-Rödelheim, after the first of these. He became a professional officer On those days, officers were sometimes operating as a mercenary leader on behalf of princes or cities, or on their own accountant
In 1608, he was employed by several Hanseatic cities and his repsonisbilities included overseeing the Dutch military architect Johan van Valckenburgh, who was employed by the same cities.
In 1610 he became governor of the city Düren in the Duchy of Jülich. He conquered the town of Schleiden, Kalkofen Castle and Brede Castle.
In 1615, he commanded troops provided by the Hanseatic League to the city Brunswick, to help them in their struggle against Duke Frederick Ulrich and on 14 October 1615, he broke the siege around the city of Brunswick.