Alfred Sisley (/ˈsɪsli/; French: [sislɛ]; 30 October 1839 – 29 January 1899) was an Impressionist landscape painter who was born and spent most of his life in France, but retained British citizenship.

Among his important works are a series of paintings of the River Thames, mostly around Hampton Court, executed in 1874, and landscapes depicting places in or near Moret-sur-Loing.

The notable paintings of the Seine and its bridges in the former suburbs of Paris are like many of his landscapes, characterised by tranquillity, in pale shades of green, pink, purple, dusty blue and cream.

From 1862, he studied at the Paris École des Beaux-Arts within the atelier of Swiss artist Marc-Charles-Gabriel Gleyre, where he became acquainted with Frédéric Bazille, Claude Monet, and Pierre-Auguste Renoir.

[1] In 1870, the Franco-Prussian War began; as a result, Sisley's father's business failed, and the painter's sole means of support became the sale of his works.

Little is known about Sisley's relationship with the paintings of J. M. W. Turner and John Constable, which he may have seen in London, but some have suggested that these artists may have influenced his development as an Impressionist painter,[7] as may have Gustave Courbet and Jean-Baptiste-Camille Corot.

[9] Described by art historian Robert Rosenblum as having "almost a generic character, an impersonal textbook idea of a perfect Impressionist painting",[10] his work strongly invokes atmosphere, and his skies are always impressive.

Among Sisley's best-known works are Street in Moret and Sand Heaps, both owned by the Art Institute of Chicago, and The Bridge at Moret-sur-Loing, shown at Musée d'Orsay, Paris.

Allée des peupliers de Moret (The Lane of Poplars at Moret) has been stolen three times from the Musée des Beaux-Arts in Nice – once in 1978 when on loan in Marseilles (recovered a few days later in the city's sewers), again in 1998 (when the museum's curator was convicted of the theft and jailed for five years with two accomplices), and finally in August 2007 (on 4 June 2008 French police recovered it and three other stolen paintings from a van in Marseilles).

On 18 June 2004 Sisley's Soleil de printemps, le Loing (1892) was restored to the family of Louis Hirsch, in a ceremony in Paris.

[13][14][15] In 2008 a dispute erupted between Alain Dreyfus, an art dealer in Switzerland, and the auction house Christie's over a Sisley painting First Day of Spring in Moret, that was claimed by the Lindon family in court in Paris.