A powerful people in the north of Gallia Belgica. They originally dwelt on both banks of
the Rhine, but were afterwards driven out of their possessions on the right bank by the
Usipetes and Tenchteri, and inhabited only the left bank near its mouth, and west of the Mosa.
Their country is described as heavily wooded, and with great swamps and marshes. They had a
fortified place on the Mosa (Meuse) called Castellum Menapiorum, the modern Cassel.