In September 1878, the Monet family moved to Vétheuil, on the banks of the Seine, around fifty kilometres downstream from Paris. The view from windows on the upper floor of the house looked southwest over a bend in the river. In the winter, the sun set behind the hamlet of Lavacourt, on the opposite shore. From his studio boat moored at the edge of the garden, Claude Monet (1840–1926) worked relentlessly on islands, the riverbank and the Seine, attentive to the changes in the landscape. While he was working on countless views over Vétheuil, the winter of 1879–1880, one of the harshest in history, provided him with a new subject and the elements for a series of twenty-eight paintings. In December 1879, plunging temperatures froze the Seine under a deep layer of ice almost 50 centimetres thick. When the thaw began in Paris, the situation quickly became catastrophic as the river transported massive blocks of ice and two bridges were swept away. Monet was fascinated by the extreme weather conditions and painted the daily evolution of this exceptional winter in Vétheuil, from December 1879 to March 1880. The snowy landscapes gave way to scenes of the frozen Seine, followed by the thaw. Fully bathed in a peaceful pink light, Winter Sun at Lavacourt was painted in the heart of winter. The composition is simple, structured around the high horizontal line that corresponds to the opposite bank of the Seine. The village in the background both separates and connects the two contrasting elements of sky and water. The long, even and parallel brushstrokes executed in the lower section of the painting accentuate the horizontal nature of the composition. The painting features a strong division, with unpainted canvas showing through in the reserved areas. The colour harmony of the landscape stems from the contrast between two complementary colours, orange and blue, in keeping with the laws of optics on the decomposition of light that have governed the work of colourist painters since Delacroix.