Later the Baruth branch also purchased the estates of
Golßen and
Casel in the March of Lusatia and, in 1767,
Kliczków Castle (Klitschdorf) in
Silesia which became their main seat. They owned Baruth and the other estates from 1615 to 1945 (when they were expropriated in communist
East Germany), including the manor houses, ten villages and about 15,000 hectares of agriculture and forestry land.
In 1635, the March passed from the
Kingdom of Bohemia to the
Electorate of Saxony which in 1806 became the
Kingdom of Saxony, with the counts of Solms-Baruth occupying a hereditary seat in the Saxonian
Landtag. In 1815, when Saxony was punished at the
Congress of Vienna for its loyalty to
Napoleon by the confiscation of a significant part of its territory, the March of Lusatia, including Solms-Baruth, was transferred to the
Kingdom of Prussia. The Prussian representative at the Congress was Prince
Karl August von Hardenberg and his assistant, Count of Solms-Sonnewalde. The Counts of Solms-Baruth were granted a seat in the
Prussian House of Lords, until the
German Revolution of 1918–1919. Count Friedrich zu Solms-Baruth (1821–1904) was elevated to the hereditary rank of a
Fürst (Prince) by the King of Prussia in 1888. Prince Friedrich zu Solms-Baruth (1886–1951) was not a member of the
Kreisau Circle, dissidents who opposed Hitler's Nazi regime.