 The region was inhabited by Celts by c. 650 BC, but it is not known whether they were aware of the local salt deposits.In 1054 Henry IV, Holy Roman Emperor gifted the area around Orb ("Orbaha") to the "Stift St. Stefan" at Mainz, it thus came under the control of the Electorate of Mainz, a part of which it remained until 1803.Bad Orb was first documented in 1059.