In Affiche ter gelegenheid van het honderdjarig jubilieum van de publicatie van De Leeuw van Vlaanderen by Alfred Ost, vibrant colors dominate the scene. The illustration features a lion, symbolizing strength and courage, set against a backdrop of rich, decorative patterns. The figures are stylized, reflecting the Art Nouveau movement's emphasis on organic forms and flowing lines.

Overall, the composition is lively and engaging, drawing the viewer's attention immediately. The artwork employs a variety of colors, primarily warm tones, which enhance its celebratory theme. The use of intricate line work and ornamental details is characteristic of the Art Nouveau style. Although the exact medium is unknown, the work likely utilizes techniques common in printmaking or poster art of the early 20th century.

The dimensions are approximately 50 x 70 cm, making it a sizable piece for an illustration. Alfred Ost was a prominent Belgian artist known for his contributions to the Art Nouveau movement. This particular work commemorates the centenary of De Leeuw van Vlaanderen, a significant literary piece by Henri Conscience that celebrates Flemish identity. An interesting fact about this illustration is that it reflects the cultural pride of Belgium during a period of national revival.

Ost's work often combines elements of nature with symbolic imagery, making it a fitting tribute to such an important literary milestone.