 Unterjeckenbach was founded in one of the later expansion phases of the Frankish taking of the land, likely in the 8th century.It originally belonged to the Nahegau, and later lay within the jurisdiction of the "Hochgericht auf der Heide" (“High Court on the Heath”), and aside from the odd period when it was pledged, it was under the lordship of the Waldgraves and Rhinegraves throughout the Middle Ages.At first, Unterjeckenbach shared its history with the neighbouring village of Oberjeckenbach.