Soir sur le Marais depicts a marsh landscape at dusk. A cluster of small houses stands along the water’s edge at the left, their steep roofs rising beside tall, slender poplar trees. Above, a pale evening sky holds scattered clouds touched with pink light, with a faint moon visible through the soft tones. Alexandre Louis Jacob frequently painted the marshlands and waterways of northern France, recording rural settlements and the low-lying landscapes characteristic of the region. Working in the late nineteenth and early twentieth centuries, he produced numerous small panels painted directly from observation, capturing subtle changes of light across water and sky. In Soir sur le Marais, the subdued palette of greys, soft blues and warm earth tones reflects the atmosphere of evening over the marshland, while the low horizon and reflective water emphasise the expansive sky above.