In 1386 the house was mentioned for the first time as the Castle of Achstetten and it was described, in 1449, as:
“a high house or waterhouse, surrounded by water with two bridges”.
The castle was then owned by the lords of Freyberg until the middle of the 17th century.
In 1525 the Achstetten castle appeared in the directory of castles which had suffered most in the peasants' revolt. A new house was built in 1538 in what is now the deer-park and in 1620 the abbot of Ochsenhausen qualified the house as lordly castle.
In the middle of the 17th century, family of the lords of Freyberg zu Achstetten died out. After this the property changed ownership several times. The owners included the noble families of Lodron, Wolkenstein, Oettingen-Spielberg and Welden.
On the 12th of May 1795, the indebted estate was purchased by Baron Beat Konrad Reuttner von Weyl. The Baron was born in 1719 in Alsace, and as knighted a member of the Teutonic Order in 1745. At the end of his successful career in the order, he was Landeskomtur of the Priory of Alace, Burgundy and Hesse, Emperioral Advisor, State minister and headed the Komturs of Marburg, Wetzlar and the Mainau.
Between 1794 and 1796 Baron Reuttner used the Italian architect, Bangato to build the present 3 storey classical castle. Francesco Antonia Bagnato (1731-1818) was the son of Givan Gaspare, who had also been the official architect of the Teutonic Order. Francesco Bangato also built a number of important churches and castles for the Teutonic Order including the churches in Oberdischingen, and Ovingen, the Teutonic Order's houses in Wangen, Überlingen and Freiburg and the castles in Achstetten, Oberkirchberg and Rimsingen. He was also involved in developments at The Orders Castle in Altshausen.
Baron Beat Konrad intended to use the castle as summer resident but he never actually lived in Achstetten, but rather in his official residence in Altshausen. So it was his nephew, Julius Caesar who was the first Reuttner to live in Achstetten. He married Mauritia Baroness v. Freyberg, and it is therefore their married crest that is on the house. In 1819 the family were promoted to the title of Count.
1981/82 the whole castle was renovated and a new park laid out. A part of it was made accessible to the public. In 1996 a fountain, which had been planned in the original design, was finally installed.
In 1847 and 1997/1998 the family also restored the family crypt-chapel, where the members of the family are buried.
Schloss Achstetten is lived in by the senior line of the family and is not open to the public. It continues to demonstrate its close ties to the community through hosting a calendar of events through the year in the courtyards and parks of the castle.
The first time the building was constructed as a crypt was in 1648 for the Baron Family Freybergs. When in 1847 the Reuttner von Weyl family decided to renovate the cemetery Chapel they also transfigured the building to the Reuttner von Weyl family crypt.
The interior structuring derived from the last major renovation which was completed in 1847. It is unsurprising that the chapel must be used sparingly and with great care and cannot meet the demands of regular use. However, the family do use the chapel both as a crypt and on occasions such as on All Saints day, where they remember their dead ancestors.
The outside restoration was initiated 1999-2000 by Countess Reuttner von Weyl with considerable financial aid from the institute for protection of historical monuments. However, unless there is the prospect of the Chapel being used more often, it is impossible to get more financial funds to restore the inside of this beautiful building.