He was born in Geldern, a city in the historical County of Gelder (now Germany). Coming to Brunant around the 1410s he took up the fight against the Venetians. In 1427 he was one of the men who attended the Convention of Grijzestad and signed the Declaration of Independence and the Grijzestad Constitution. Hieronymus became the pater familias of a noble family who would become, in 1512, Dukes of Helmond.
Van der Ecke was married in 1504 to Luise Van Dort and he had two sons, Philip and Christian.