After training in Antwerp, he spent his entire career abroad, first in Northern Italy and later in Vienna and other cities in central Europe.
[3] He was part of a network of Flemish and Dutch painters working for the court, aristocracy and ecclesiastical institutions of central Europe.
On 18 October 1648 he joined the 'Sodaliteit van de Bejaerde Jongmans' (Sodality of the Unmarried Men of Age), a fraternity for bachelors established by the Jesuit order.
[6] He left Flanders and was subsequently recorded in Northern Italy, where he was documented in Lovere in 1657 as working on an altarpiece for the local church of St George.
In this location he resided long enough to train the painter Angelo Everardi, who was likely of Flemish descent and was known as il Fiammenghino.
It is likely that the artists knew each other as they both contributed to a collaborative book published in Vienna, the Historia di Leopoldo Cesare.
[8] Jan de Herdt followed in the footsteps of many of his compatriots of the previous generation who sought a career in Central Europe.
The Southern Netherlands had developed a close bond with the Imperial court in Vienna as its Spanish Habsburg rulers were connected with it through dynastic links.
On that date he signed his name in the ecclesiastical registers of the Schottenkirche (Scottish church) in Vienna as he together with the Flemish engraver Franciscus van der Steen acted as a witnesses at the wedding of the Dutch artist Hans de Jode.
Jan de Herdt later collaborated with van der Steen on a series of aristocratic portraits for the publication Historia di Lepoldo Cesare.
The most apparent influences on his work are Antwerp's leading painters Anthony van Dyck, Rubens, Jordaens and Caspar de Crayer.
This is shown in his Portrait of the family of Imperial Goldsmith Franz Wilhelm de Harde von Antorff (Royal Museums of Fine Arts of Belgium).
Jan de Herdt along with the above-mentioned artists created an entirely new visual language in Central Europe through this type of communicative group portrait.
[5] For instance, the Portrait of the Polish nobleman and commander Jerzy Sebastian Lubomirski (Royal Castle, Warsaw) was attributed in this manner.
In 1920 the artist's signature was discovered on the altarpiece of the high altar of the Church of Saint Maurice in Breno in Lombardy, northern Italy.
[14] Another painting by de Herdt in Lombardy is an altarpiece of Moses striking the rock preserved in the Church of Saint Georges in Lovere.