Commissioned by the painter James Pitcairn-Knowles, the architect Paul Schultze-Naumburg built Freudenberg Castle in 1904/05, a building on an almost square ground plan in the style of the villas designed by the Italian Renaissance architect Andrea Palladio. The façades of the compact building are strictly symmetrical and are emphasized by three-axis central risalits with flat triangular gables. The 50 or so rooms are grouped on four floors around the spacious entrance hall, which also houses the main staircase with a three-flight wooden staircase.

The builder only lived in the castle for a few years. In 1909, he sold it to Baroness Mathilde von Entreß-Fürsteneck. In the following years, Freudenberg Castle changed hands several times. In 1925, the district and the city of Essen acquired it to establish a recreation home. From 1933, it was run by the Essen NS Women's Association and the NS People's Welfare Association. In 1939, the Wiesbaden army base administration took over the castle. From 1945-65, Freudenberg Castle was requisitioned by the American military. It was bought by the FRG in 1965. In 1974, Schloss Freudenberg was leased to the Pentecostal Church International, which used it as a training center. In 1975/76, a comprehensive renovation and reconstruction took place. In 1990, the estate became the property of the city of Wiesbaden.

Since 1993, the castle and park have been used by the Society and Association for Nature and Art, which took over the leasehold for 66 years from 2005. In 2008, the Schloss Freudenberg Foundation was established within the German Foundation for Monument Protection in order to continue the restoration of the building.