Dies was born in Hanover (baptized 11 February 1755), and began his studies there. For one year he studied in the academy of Düsseldorf, and then he started at the age of twenty with thirty ducats in his pocket for Rome, studying briefly on the way in Mannheim and Basel. In Rome he lived a frugal life till 1796; his son Johannes (Giovanni) was born there in 1776. Copying pictures, chiefly by Salvator Rosa, for a livelihood, his taste led him to draw and paint from nature in Tivoli, Albano and other picturesque places in the vicinity of Rome. Naples, the birthplace of his favorite master, he visited more than once for the same reasons.