Jan was the son of Gerald van de Werve, 5th Lord of Hovorst.
He married three times with ladies of noble birth: 2nd with Claire Rockox.
He became the uncle of Nicolaas II Rockox and Jacobus Dassa, all mayors of Antwerp.
Van de Werve studied canon law, and followed his father in a career of service to the city of Antwerp, serving numerous terms as an alderman between 1533 and 1570.
He wrote a Dutch dictionary, Den schat der Duytscher talen, which was first published in 1553 and went through many editions.