Amedeo Modigliani’s Nu assis au collier led Sotheby’s London June sales this week, selling for £48.2 million with fees — about $63.5 million to $63.9 million — as works from the Lewis Collection helped deliver one of Europe’s strongest auction nights of the year.

The Modigliani was the top lot in Sotheby’s Masterpieces from the Lewis Collection sale, a high-profile dispersal of works assembled by billionaire financier Joe Lewis and his daughter Vivienne. The single-owner auction totaled £296.3 million with fees, or roughly $392.6 million, according to multiple market reports citing Sotheby’s results. A second modern and contemporary evening sale brought the house’s combined London total for the night to £393.4 million, or about $520.7 million.

The outcome gives the U.S. art market a fresh data point after a period in which New York has continued to dominate the highest end of public auctions. London’s ability to produce a nine-figure evening around a private collection matters for American collectors, art advisers, museums, lenders and estates because pricing for trophy modern and postwar works is set across a small circuit of global salesrooms. When a Modigliani, Klimt, Freud or Picasso changes hands at this level in London, the result can echo into valuations and private negotiations in New York, Los Angeles, Palm Beach and Silicon Valley.

Nu assis au collier, executed in 1917-18, was cataloged by Sotheby’s as an oil on canvas measuring 91.5 by 59.7 centimeters. The work carried an estimate available only upon request on Sotheby’s public lot page, but pre-sale reporting placed expectations above £45 million. Its sale price landed above that level once fees were included, making it the evening’s most visible benchmark for demand at the top of the market.

The painting also carried art-historical weight beyond its price. It belongs to the group of Modigliani nudes associated with the artist’s brief and controversial 1917 Paris exhibition, which was shut down by police on grounds of indecency. Those nudes have since become among Modigliani’s most recognizable and commercially powerful images. Other paintings from the same period have crossed the $100 million threshold at auction in New York, reinforcing why a London appearance by Nu assis au collier drew international attention.

The Lewis Collection result was notable because the sale was not built around guarantees, according to art-market reports. Guarantees can reduce risk for sellers and auction houses but may also make it harder to read the depth of competitive bidding. In this case, the absence of guarantees made the total more closely watched. Only one of the 25 Lewis lots failed to sell, while several works exceeded expectations, giving Sotheby’s a strong public result at a time when the upper tier of the auction market has been selective rather than broadly exuberant.

Among the other major works, Gustav Klimt’s Bildnis Gertrud Loew, also known as Portrait of Gertrud Loew, sold for £36.2 million with fees, or about $47.9 million. Lucian Freud’s Sleeping by the Lion Carpet sold for £29.3 million, or about $38.8 million. Edgar Degas’s Petite danseuse de quatorze ans sold for about £25.1 million, while René Magritte’s La Belle promenade rose sharply above expectations to £16 million. Those results helped broaden the sale beyond a single trophy lot and showed demand across European modernism, Surrealism and postwar figuration.

The collection’s composition was central to its appeal. Sotheby’s catalog listed works by Gustave Caillebotte, René Magritte, Pablo Picasso, Henri Matisse, Edgar Degas, Kazimir Malevich, Egon Schiele, Max Beckmann, Lucian Freud, Francis Bacon, Gustav Klimt, Chaïm Soutine, Kees van Dongen and Marc Chagall, among others. That range gave the evening a museum-like structure, moving from late 19th-century and early 20th-century modernism into the School of London and postwar figurative painting.

For U.S. readers, the sale also intersects with the long-running movement of major private collections through global auction houses. Lewis acquired some works through the New York trade, including Modigliani’s Nu assis au collier, which had last sold at Christie’s New York in 1995 for $12.4 million, according to Artnet. That provenance trail illustrates how trophy artworks often circulate between American and European salesrooms over decades, with each public sale resetting the reference price for advisers and collectors.

The auction also underscored the importance of Asian buying to the market’s top end. The Art Newspaper reported that Asian collectors bid on about half of the Lewis lots and accounted for around a third of the auction total, citing Sotheby’s. That pattern is closely watched in the United States because New York auctions rely heavily on cross-border bidding from Asia, Europe, the Middle East and Latin America. A strong London night with international participation suggests that demand for the most recognizable modern works remains global, even if buyers are more disciplined on price.

The broader Sotheby’s total of about $520.7 million for the double-header also helps London’s cultural-market narrative. The city has faced persistent questions about whether Brexit, tax policy and competition from New York, Hong Kong and Paris have reduced its standing as a premier auction hub. A single evening anchored by a private collection from a British billionaire does not settle those questions, but it does show that London can still produce a globally watched auction event when the material is rare, fresh and institutionally recognizable.

The sale arrives as the American art market is also watching the supply of major private collections. Large single-owner sales can concentrate attention, draw international specialists and establish price signals that smaller consignments cannot. For museums, the public sale of a collection of this scale can also affect exhibition loans and future access, because works that had been held privately for years may move into different hands, sometimes disappearing again from public view.

Sotheby’s now leaves the June London cycle with a stronger market signal than many expected earlier in the season. The Modigliani’s roughly $63.5 million result did not approach the artist’s nine-figure New York records, but it succeeded in its assigned role: anchoring a major sale, validating the Lewis Collection’s appeal and giving London a moment of relevance in a market often measured against Manhattan. For U.S. arts and culture observers, that makes the result less a foreign auction footnote than a cross-border pricing event for the global modern-art economy.