NEW YORK - A kaleidoscopic 1915 Marsden Hartley painting, seized during World War II and cloistered for 54 years in a German museum, sold for a record $6.3 million yesterday at Christie's International in New York.

Hartley's colorful

Lighthouse

was the most expensive American modernist artwork ever sold at auction, edging past Georgia O'Keeffe's

Calla Lillies With Red Anemone

, which sold for $6.2 million at Christie's in 2001.

The sale price, $700,000 below the top estimate, also set a record for the artist, whose previous auction record was $2.8 million for

Painting No. 6

, sold at Sotheby's in 2002. The price includes commission.

Hartley painted

Lighthouse

during a stay in Berlin between 1913 and 1915, one of his most fertile periods. A layered construction of abstract shapes, jags and swirls, it illustrates his experimentation with cubism, German expressionism, American Indian motifs, and military symbols. A tall, red lighthouselike form anchors the canvas' center.

"Hartley was creating painting like no other American at the time," said Bruce Weber, a curator at New York's National Academy. "He was out there making his own work, creating his own style."

The painting was lost to art historians, who knew of it only from letters between Hartley and his New York dealer, Alfred Stieglitz. Hartley, always broke, was elated to sell it to German publisher Wolfgang Wachsmuth Harlan, who bought four Hartleys in 1915, according to Christie's catalog.

Sometime before 1929, Harlan sold

Lighthouse

to collector Hans Hasso. The Soviet military confiscated it in 1945. Nine years later, it reappeared at the Stiftung Moritzburg museum in Halle, East Germany, where it remained until this year, when it was returned to Hasso's grandson in February. He consigned it to Christie's for sale.

The Maine-born Hartley had his first exhibit in 1909 at Stieglitz's New York avant-garde gallery, 291. He traveled to Europe in 1914.

The Hartley was sold at Christie's American painting sale, which totaled $72.6 million, the firm's highest for the category. About 20 percent of 140 lots failed to sell.

The auction tested the domestic art market's strength. American 19th- and early-20th-century art is collected mostly by U.S. buyers. The top of the market soared, while lesser works by John Singer Sargent and Mary Cassatt with aggressive estimates were among the casualties.

Western art was especially popular. Thomas Moran's majestic 1878

Green River of Wyoming

sold for $17.7 million, setting a record as the most-expensive 19th-century painting sold at auction, according to Christie's. The Moran was the sale's priciest lot and sold for triple its $5 million high estimate. It was on loan to the Woolaroc Art Museum in Bartlesville, Okla., from 1978 until this year. The buyer was Richard Rossello, of Bryn Mawr's Avery Galleries, who said he made the purchase on behalf of a client.