Naiads Filling the Horn of Achelous. Allegory on the peace of the 12 years Truce,

Janssens's Naiads Filling the Horn of Achelous, painted in 1610 as an allegory for the Twelve Years' Truce, is one of his most elaborate mythological works. The myth of Achelous — the river god whose broken horn was filled by nymphs with fruits and flowers, becoming the first cornucopia — was an apt choice for a peace allegory: the truce between Spain and the Dutch Republic ended years of warfare and opened the possibility of renewed agricultural and commercial abundance. The Royal Museums of Fine Arts of Belgium hold the work as a major example of Antwerp allegorical painting at its most ambitious. Janssens combines mythological narrative with political allegory, a Baroque formula that allowed learned patrons to interpret the subject simultaneously as classical mythology and contemporary commentary. The River Scheldt connection — Achelous as a river deity — links the allegory to the commercial geography of Antwerp itself.

Canvas with a multi-figure composition of water nymphs and the river god Achelous organized around the central action of filling the horn. The horizontal landscape format accommodates the aquatic setting: a river bank or stream edge with figures distributed across it in natural, relaxed poses. Water, wet hair, and luminous wet skin challenge and display Janssens's technical abilities. The cornucopia's contents — fruit, flowers, grain — are rendered with botanical precision.