While his works were believed to be authentic 15th-century Spanish paintings or illuminations, the Spanish Forger - a name derived from the nationality wrongly assigned to him - was unmasked in 1930 by Belle da Costa Greene, director of the Pierpont Morgan Library in New York. Having successfully deceived numerous experts and collectors until that date, the Spanish Forger is now recognized as one of the most talented and prolific forgers in history, so much so that a monographic exhibition was dedicated to him at the Pierpont Morgan Library in 1978. Today, his works are studied, collected, and appreciated for what they truly are: fakes. The Spanish Forger’s art illustrates in a unique and remarkable way the history of the art of deception, the history of the art market, and the history of the taste for the Middle Ages, which, at the time the Spanish Forger was active, fascinated a vast public with its fanciful imagery.

The present illumination depicts the Ascent to Calvary within a large initial 'A', crowned with scrollwork and floral ornaments. Before an architecture intended to represent Jerusalem, from where Christ departs to begin his journey to the cross, Christ is placed at the center, supporting the cross on his right shoulder. He receives the sudarium, upon which the Holy Face has appeared, handed to him by Saint Veronica. Full of dynamism and movement, the illumination is enriched by the numerous figures: to the right, four holy figures, including the Virgin in blue and Saint John behind her; to the left, soldiers and executioners, one of whom, in the foreground dressed in red, pulls Christ by a rope. A soldier on horseback heads toward Golgotha, indicated by the small hill in the background.

Acquired around 1950 as an authentic medieval illumination by a Swiss family based in Lucerne, the present miniature is, like the majority of the Spanish Forger's works, painted on an authentic fragment of parchment. The use of a 15th-century support naturally contributed to the deception, but the painting itself is entirely inauthentic. Scientific studies on the Spanish Forger's works have demonstrated the presence of pigments that did not appear until the 19th century. The gold leaf was intentionally cracked by the artist to give his work an aged appearance, and certain iconographic details, such as the presence of castles in the landscape, beasts in the secondary decoration or mix of religious and secular details, were intended solely to lend a medieval air to the illumination. Stylistically, the Spanish Forger freezes his figures within the composition, clothes them in long, deeply folded draperies or shining armor, and gives them all the same repetitive expression in an attempt to imitate the stylistic codes of the Middle Ages. However, the soft, round faces of the female figures and their low necklines are in no way medieval, and certain iconographic elements are troubling, if not purely mistaken, such as the perfume jar of Mary Magdalene held by a male figure in the Deposition scene, or the female figure in red behind Christ making the gesture of Christ pantocrator in the present miniature.

For now, the true identity of the Spanish Forger remains a mystery. One identification hypothesis was proposed - that of the Belgian painter Ferdinand Charles François Joseph de Pape (Bruges 1810–Bruges 1885) and his son Charles (who joined his father's workshop in 1859 and died in England in 1915), key figures in the revival of medieval illumination in Belgium. However, this identification is not unanimously accepted, mainly because it is now clear that the Spanish Forger was active in Paris between around the 1890s and the 1930s: remnants of old Parisian newspaper were found in his frames, and several of his compositions were freely inspired by chromolithographs published in the French capital at the time. All evidence suggests that the Spanish Forger was likely employed by a French publishing house, but his name remains to be revealed.