[3] Ottenhausen absorbed the hamlet Rudmersbach which was mentioned initially in 1292 as 'Rutmerspach'[4] Around the year 1000 the Counts of Calw had a fortress built near today's village of Neuenbürg-Dennach.

The fortress was called Straubenhardt after the inhospitable area (Alemannic: "Struben Hardt" - rough forest).

The Schmalensteiners who were related by marriage to the Lords of Straubenhardt and who also lived at the fortress, therefore joined a Federation of the Knights under the leadership of Wolf von Eberstein.

In 1367 the Federation of the Knights committed an assault on Count Eberhard II of Württemberg while he was staying in Wildbad.

It is suspected that the nobles of Straubenhardt initiated the foundation of the villages Conweiler, Feldrennach, Langenalb, Schwann as well as Arnbach, Dennach, Dobel, Neusatz and Rotensol.

[8] The discovery of a relief of the hunting goddess Diana, found in the wall of the rectory of Ottenhausen, indicates an early Roman settlement in this area.