One of the most sensational naval battles of the American Civil War took place off the coast of France. The Federal corvette Kearsarge sank the Confederate ship Alabama near Cherbourg on June 19, 1864. Manet, a former sailor, was captivated by the reports in the Parisian press and rushed a painting of the battle (now in the Philadelphia Museum of Art) to a dealer's window. A few weeks later, during his habitual summer vacation at Boulogne, Manet was keen to see the victorious ship, which was being provisioned and repaired. He wrote a friend: "The Kearsage [sic] was anchored at Boulogne last Sunday. I went to have a look. I had got it about right. So then I painted her as she looked on the water. Judge for yourself."

This picture is the result. It is the first in a series of seascapes that would profoundly affect the course of French painting. Here, Manet introduced several pictorial devices—the bird's-eye perspective, the reduction of sea and sky to flat, flaglike bands of color, and the boats' inky silhouettes—borrowed from Japanese woodblock prints, an art form that had only recently come to his attention. Monet quickly followed suit. Soon French critics would identify the founding of Impressionism with the assimilation of Japanese art into contemporary painting.