Painted in 1891, October Night dates from a key period in Denis' career when he began to adopt a more synthetic approach. He belonged to the young Nabis group who, as Jean Verkade testified, were concerned primarily with decorative painting: "a war cry circulated from studio to studio: no more easel paintings […] only decorations remain".
In 1892, this piece was exhibited at the 8th Salon des Indépendants, together with three other paintings – September Night, April and July – to make up a series entitled Poetic Subjects (four panels for the decoration of a girl's room). Although the series did not include Winter, it was often interpreted as a Seasons cycle, a theme already taken up by Poussin, Boucher, Cézanne and others, and which Vuillard would go on to tackle in 1892. The series could also be considered as the symbolic representation of four moments in a woman's life, October Night being that of engagement, the young woman in pink probably representing the Denis’ betrothed, Marthe Meurier, accompanied by her sister, Eva. This decidedly symbolist scene could, then, be a token for the young artist’s fiancée through which he expressed his feelings for her.
The palette of pearly and rich bronze tones, treated in gradations, creates a delicate colour field which contributes to the overall feeling of serenity. With his subtle play on the arabesques of the female silhouettes and the Japanese-inspired network of veins on the bark of the chestnut trees, Maurice Denis shows himself here to be one of the originators of Art Nouveau.