Amanadeutsch ( German Amanadeutsch ; also - colonial German , Kolonie-Deutsch ) is a language , a dialect of German language , belonging to the West-Middle German group of High German dialects . Since the 50s of the XIX century it has been used in the area of the colony of Aman , Iowa , USA . The settlements of the colony were founded by radical pietistic emigrants from several German-speaking countries , primarily from the land of Hesse . They took the Hessian dialect as the basis of their language and managed to preserve it. Being inspirationists , they had virtually no contact with the world around them, which allowed their language to remain free from all outside influences until the 1930s . After this time, for various reasons, the inhabitants of the colony shifted closer to the outside world.