Oskar Bergman occupies a unique position in Swedish art history through his detail-rich, atmospheric landscape paintings of primarily Swedish nature and Swedish towns in bright colours and shimmering light. With a strong influence from the Swedish Artists' Association's national romanticism and Japanese woodblock printmaking, he developed his distinctive visual language. He primarily worked in gouache and watercolour, mediums that allowed for a high degree of control and precision in execution.

His motifs are often drawn from the areas around Saltsjöbaden, where he spent much of his life, but his works transcend the documentary. Instead, the landscapes serve as subjects of study where he explores form, rhythm, and composition. With restrained colour palettes and a carefully constructed pictorial structure, he creates a visual order where each element is balanced. Oskar Bergman's art can be understood as an extension of the national romantic landscape painting, but with a personal interpretation that approaches the decorative and sometimes symbolic. Through his methodical working process and focus on the formal qualities of nature, he contributed to a continuity within Swedish figurative painting during the first half of the 20th century.