KAMAISHI, Japan » The requests to see her perform had dwindled over the years. But when the earthquake struck at 2:46 p.m. on March 11, this city’s last geisha was, fittingly, at home getting ready to sing that night at Kamaishi’s 117-year-old ryotei, an exclusive restaurant featuring fine food and entertainment where she began working as a 14-year-old seven decades ago.

She had already put on the white split-toe socks she would wear with her kimono and was preparing to put her hair up. Hired to entertain a party of four in honor of a colleague’s transfer from Kamaishi, she had picked just the right song, one meant to steel young samurai going to their first battle.

But a tsunami would engulf this city within 35 minutes and, as Kamaishi trembled from at least 15 big aftershocks during that short time, the geisha, Tsuyako Ito, 84, fought to survive. She had lived through three tsunamis before in Kamaishi, a place that the waves have destroyed with regularity over the centuries, and as a girl she had listened to her grandmother’s tales of the great 1896 tsunami.

“My grandmother said that a tsunami is like a wide-open mouth that swallows everything in its path,” Ito said from a local hospital where she was being treated for asthma, “so that victory comes to those who run away as fast as possible.”

Her mother carried her on her back to safety at the time of Ito’s first tsunami in 1933. This time, after her legs gave out, an admirer carried Ito on his back to higher ground. Ito, who had planned to retire on her 88th birthday, a milestone in Japan, survived her fourth — and “most frightening” — tsunami.

The waves, however, swept away her shamisen, a three-stringed instrument, and kimono, the two tools essential to a geisha’s art.

The recent tsunami is believed to have killed about 1,300 people in Kamaishi, whose low-lying areas have been transformed into a dusty ghost town where the smell of ruined buildings now mingles with that of the sea.

The birthplace of Japan’s steel industry, Kamaishi played a key role in the country’s modernization and militarization, so that it became the first target on mainland Japan of U.S. warships during World War II. During Japan’s postwar boom, the city’s population swelled as it easily overcame the ravages of two tsunamis.

Kamaishi became famous for its delicious seafood, the winning ways of its main employer’s rugby team, Nippon Steel, and its diversions.

As Japan’s fortunes have declined in the past two decades, Kamaishi’s fall has been faster and steeper.

Its population, nearly 100,000 two generations ago, has now fallen below 40,000 and is aging. Many who have lost homes and businesses here are not expected to remain.

Ito vowed to sing and dance again in Kamaishi. A famous beauty, she both danced and played the shamisen, while most geishas were only skilled at playing the shamisen, said Setsuko Kanazawa, whose family owns Saiwairo, the ryotei where she performs.

To cultural preservationists here, she is the guardian of a local culture that was fast disappearing.

The last ryotei in Kamaishi, Saiwairo was also its most exclusive. It was built in 1894 on the most elevated point of an area that would be dotted with bars, brothels and other ryoteis. While tsunamis washed away Saiwairo’s neighbors, they never reached its first floor.

It was at Saiwairo that Ito began an apprenticeship at the age of 14.

“I loved to dance,” she said. “And I simply wanted to become a leading geisha in Kamaishi.”

The truth, whispered for decades inside the family home, was darker, said Satoshi Ito, Ito’s nephew. Ito’s father ran a small-time construction business and, her nephew said, had ties with Japan’s gangsters, the yakuza.

“He would repair roads here and there, using yakuza to control certain areas,” said Satoshi Ito, 63, who lived with his aunt here but is now staying at an evacuation shelter.

“Her father is supposed to have told her she was suited for that life,” he added. “But to put it harshly, I think that he did it to guarantee some debts.”

After a marriage to a sushi restaurant owner, the birth of a daughter and a divorce, Ito went to Tokyo to study dance under a famous instructor. Back in Kamaishi, Ito and a dozen other geishas were constantly on call at this city’s ryoteis, as Kamaishi’s economy began booming in the 1950s. At Saiwairo, steel industry executives occupied some rooms as owners of fishing vessels partied in others, Kanazawa said.

But Kamaishi’s economy peaked a decade before Japan’s did, as the city’s two main industries began declining in the 1970s.

Nippon Steel began moving its operations out of Kamaishi, eventually closing down its blast furnaces in 1989; fishing shrank as new rules on exclusive economic zones kept Kamaishi’s fishing vessels closer to Japan.

In 1978, the central government began building the world’s deepest and most expensive breakwater in Kamaishi’s harbor, a plan intended to protect the city against tsunamis as well as to create jobs.

But the breakwater, which took 30 years to complete, did little to stop Kamaishi’s economic slide. What’s more, after Japan’s economic bubble burst two decades ago, company executives could no longer hire geishas on their expense accounts, said Kanazawa of Saiwairo.

Saiwairo opened its doors to a larger public, first as a new venue for weddings; in recent years, in a reflection of this city’s aging population, it has become a popular setting for memorial services.

“We couldn’t survive on pride alone,” Kanazawa said.

Still, sometimes the calls came for Ito, some from old customers, others from new customers reflecting the world’s new economic order.

“About once a month,” Satoshi Ito said of the frequency of his aunt’s performances. “Chinese industrialists, among others, now come here.”

And so on March 11, as Ito was getting ready to perform, the biggest tsunami of her life assailed Kamaishi, tearing apart the breakwater and eventually reaching inland all the way to the house where she and her nephew lived.

As it turned out, after a wall in her house collapsed and she slowly moved to flee, Hiroyuki Maruki, 59, a sake store owner and the president of a group dedicated to preserving an old melody called “Kamaishi Seashore Song,” came by looking for her.

“She is the only one who knows how to sing that song,” Maruki said.

As Maruki carried Ito up a hill, she recalled “feeling the soft warmth of his back.”

Maruki said, “I thought she’d be light, but she was surprisingly heavy. I wondered at one point what was I going to do.”

Having survived yet another tsunami, Ito said that her regret was that she had been unable to sing that night.

“I’d practiced the night before, and after putting my thoughts together, I thought this song would be all right,” she said, explaining that the song told the story of a young samurai on horseback going to his first, long-awaited battle.

“It ended without my singing,” she said. “It’s such a nice song, too.”

© 2011 The New York Times Company