Unlike his family members, he is mainly known for his large-scale compositions with many swirling figures depicting scenes from ancient history or mythology.
[6] Gillis van Valckenborch received his earliest training in Antwerp possibly from his brother Frederik.
Just like his brother Frederik he was required to undergo a theological test before he was admitted as a burgher since they were suspected of being Gnesio-Lutherans.
[9] Gillis van Valckenborch painted biblical and mythological scenes and figures, as well as protagonists from Greek and Roman history set in landscapes.
[3] He drew inspiration from the innovative works by the School of Prague such as Bartholomeus Spranger and the movement of international Mannerism.
[10] Two pendant works depicting a scene of a fire in a village in the National Gallery of Slovenia have been attributed to van Valckenborch based on the traditional record Valkenburg, with which the paintings were catalogued in the Landesbildergalerie in Graz, on the style, and also on the motif.
That fire was one of his favourite motifs is testified by a lost painting said to have depicted The Burning of Troy, which was also in the Herzog Anton Ulrich Museum until 1714.