As part of the West Hesse Depression, it lies in a sunken area that was formed by volcanic activity in the Tertiary sub-era.

There were settlers in the Felsberg region, as long ago as the last ice age, as witnessed by the find of the 12,000-year-old, so-called Rhünda Skull.

The only mention of the area from this time is a report by the Roman historian Tacitus about one of Germanicus's campaigns, when in the year 15 he destroyed Mattium (probably nowadays Maden), the Chatti's capital.

The castles were built in the Middle Ages for their strategic locations, during the feud between the Archbishopric of Mainz and the Landgraviate of Thuringia, or Hesse.

In 1090, Felsberg was mentioned in a Mainz document under the name Velisberc, and again under the same name in 1209 in a good's directory from the Petrus Estate in Fritzlar.

In the Second World War, Felsberg was heavily damaged by aerial bombardment and the destruction of the Edertal Dam.

The last two municipal elections gave the following results: The town executive (Magistrat) consists of 14 councillors and the mayor.