LONDON.- An important work by Henri Matisse (1869-1954), Nu (femme) debout – unseen since it was exhibited in 1981 – leads Bonhams’ Impressionist & Modern Art sale on Tuesday 23 November at New Bond Street, London. The work has been in the same private collection since 1977 and has an estimate of £1,800,000 - 2,500,000.

Nu (femme) debout – Standing Nude – was first acquired by two of Matisse’s greatest friends and patrons, Michael and Sarah Stein. Michael was the brother of Gertrude and Leo Stein, and together they were some of the most pre-eminent collectors of Modern Art in Paris during the early 20th century.

Bonhams Global Head of Impressionist and Modern Art, India Phillips, commented: “Nu (femme) debout dates from the pinnacle of Henri Matisse's Fauvist period when his unbridled use of colour and handling of pigment was at its most radical and liberated. The work was acquired shortly after completion by Michael and Sarah Stein, who were among the most significant patrons of Matisse’s early career. It is a rare example of Matisse’s figurative Fauvist work outside a museum collection.

“It was also one of the first three works by Matisse seen in America, and it helped – along with the astounding efforts of Sarah Stein – to secure Matisse's name internationally as being linked with the development of modern art. With the remainder of the Michael and Sarah Stein collection now widely scattered, the emergence of this work onto the auction market marks an incredible opportunity to own a work so personally intertwined with the artist and his patronage by the formidable Stein family.”

The work has been included in a number of important museum exhibitions, including MoMA, New York, and Grand Palais, Paris. It has been requested for inclusion in the forthcoming exhibition Matisse: Life & Spirit, Masterpieces from the Centre Pompidou at the Gallery of New South Wales in Sydney.

The Stein siblings were born in Pennsylvania to wealthy parents and by 1904, all three of them were living in Paris. Originally planning to stay in France for just a year, Michael and his wife, Sarah, would remain there for more than 30 years and together with Gertrude and Leo, the four build the era's foremost collection of modern art.

Introduced to artists through Leo and Gertrude, Michael and Sarah were quick to embrace modern art, buying works by Gauguin, Picasso, and Matisse. Nu (femme) debout was painted in the immediate aftermath of the infamous Salon d'Automne of October 1905. The exhibition, which appalled the French public and gave birth to the Fauvist movement, not only secured Matisse's position as the leader of the Parisian avant-garde, but crucially marked the beginning of a profound relationship between him and the Steins. Painted in late 1905 to early 1906, the work has been identified by the Matisse family as Michael and Sarah's ‘first purchase’ and was exhibited in Matisse's second one-man show at the Galerie Druet in 1906.

The work is clearly identifiable in a number of photographs taken of Michael and Sarah Stein's home on rue Madame between 1908-1914. The photographs also reveal the full breadth and quality of works by Matisse within their collection – nearly all of which are now in museum collections.

Michael and Sarah Stein kept Nu (femme) debout in their collection for more than four decades. The work remained with the family following their permanent return to California in 1935, and the death of Michael in 1938, and was likely only sold for financial reasons in the mid-1940s.

Sarah's patronage of Matisse would continue following Michael’s death – she made her Palo Alto home open to anyone interested in the artist. When she was forced gradually to disperse her collection before her death in 1953, she chose to burn most of her letters from Matisse to prevent what she feared would be a misunderstanding over her relationship with the artist.

Nu (femme) debout will be on view at at Bonhams Hong Kong from 3 - 10 November, where it will be displayed alongside Foujita’s Nu Allongé. It will come to Bonhams New Bond Street, London, for the full sale view from 20 - 23 November, the day of the sale.

Other highlights of the sale include:

• Giorgio Morandi (1890-1964), Natura Morta. Painted in 1954. Estimate: £800,000-1,200,000.

• Léonard Tsuguharu Foujita (1886-1968), Nu Allongé. Painted in 1932. Estimate: £800,000-1,200,000.

• Auguste Rodin (1840-1917), Age d'Airain, petit modèle dit aussi '2ème réduction'. Conceived between 1875-1877, this reduction from November 1904. This bronze version cast by the Alexis Rudier Foundry in November 1943. Estimate: £150,000-200,000.