Rittershausen has 952 inhabitants, representing 14.2% of Dietzhölztal's population (as of 31 December 2005), making it the constituent community with the smallest population, but with a rural area of 1 847 ha (Dietzhölztal: 3 744 ha), that is, 49.3%, Rittershausen is almost as big as the three other communities of Ewersbach, Mandeln and Steinbrücken put together.

A landlord named Lager and his wife Duda donated to the Nazarius Monastery at Lorsch (near Heppenheim) under Richbodo's abbacy three farmyards, as many subsistence farms and five bound farmers in Mauventelina (Mandeln) in the Perfgau, whose political and ecclesiastical centre was Breidenbach.

A greater than average rise in population was seen in the 1970s due to the eviction of the weekend cottage area of Ebachseite and the arrival of guest workers' families.

The old form of the name, Rudershusz, the favoured location in the Dietzhölze Valley, and the village's persistence even during the period of abandonments (due to an agrarian depression) in the Late Middle Ages all suggest that Rittershausen was founded in the 9th century, or at the latest, the 10th.

About 1912, the Reverend Karl Nebe, with sponsorship from councillor of commerce and local landowner Gustav Jung, and under the leadership of the State Museum in Wiesbaden, carried out a number of digs around the Ley (≈ cliff or crag).

Rittershausen's first documentary mention came in 1344 when the Mann- und Zinsbuch der Herren von Bicken ("Man and Interest Book of the Lords of Bicken") mentioned that in Ruderszhausen disz seyt der Bach (ie "this side of the brook"), the Lords were entitled to Groß- und Kleinzehnt (great and small tithes).

Nobody quite knows when these places were abandoned, but according to the aforesaid Reverend Karl Nebe, who was reporting local oral history, Langenbach was destroyed by the Plague, and the last few survivors moved to Rittershausen.