HAMBURG.- It’s among the longest tenures of any director of an arts organization. Choreographer John Neumeier has been running the Hamburg Ballet for 51 years, transforming it from a provincial opera house troupe into an international vehicle for his work — a prolific mix of abstract and storytelling ballets that draws fervent audiences at home and abroad.

On Sunday, Neumeier will take his final bow as director, at the company’s annual end-of-season Nijinsky Gala, at which extracts from 13 of his works will be performed. After that Argentine choreographer Demis Volpi will step into the role of artistic director.

Neumeier is 85, which might seem like a decent age to retire. But choosing to go was difficult for him.

“It was a rational decision, not an emotional one,” he said hesitantly in an interview in April at his home, a light-filled, early 20th-century villa in a quiet suburb of Hamburg. Trim and dapper in sneakers and a plaid shirt, Neumeier speaks with quiet focus and still moves with a dancer’s ease.

“If I asked myself, are the dancers unhappy, are they bored, I have to say I didn’t feel any of that,” he said. “But when I started approaching 50 years here, I thought, I don’t want a downward slide.” He looked momentarily tearful. “The hardest part is looking at the young people coming up, that’s the most beautiful part of your work, feeling that you are contributing to them.”

Neumeier is American, born in Milwaukee, and strongly influenced by his early training with the experimental modern dance choreographer Sybil Shearer in Illinois. But his career has been in Europe, where he is counted as a major figure in ballet who has created more than 170 works, many in company repertories around the world.

“In Germany he is more or less the pope of ballet,” said Manuel Brug, a critic for the German newspaper Die Welt. “He is loved, no one is saying he should have gone 10 years ago.”

Neumeier, said Christian Spuck, the artistic director of the Berlin Staatsballett, “made Hamburg a ballet town, with the company, the school, the youth company. He is famous for his workshops, his connection to the audience who love how he explains his work and shares it with them. Everyone — but everyone — in Hamburg knows John Neumeier.”

He is far less known in the United States, although the Hamburg Ballet toured fairly frequently there in the 1970s and ’80s, to generally approving reviews, and many of his pieces have been performed by American companies. But more recent reviews from the United States and Britain have often been dismissive, criticizing Neumeier’s musicality, penchant for literary subjects and choreographic choices. Perhaps, Brug said, because the Anglo-Saxon ballet tradition is “either old-fashioned storytelling or very abstract, and what Neumeier does is something in between, more like a collage.”

Neumeier, whose mother was of Polish origin and father from a German family, began tap dance classes at 9 and started ballet a year later. At 11, he discovered Anatole Bourman’s “The Tragedy of Nijinsky” at the library, and a lifelong fascination began. Almost since that age, Neumeier has been collecting books, images, sculptures and anything else connected to Vaslav Nijinsky, the Polish-Russian dancer and choreographer whose comet-flare career (and descent into schizophrenia) was a pivotal point in early 20th-century dance.

Neumeier’s house is the site of the John Neumeier Foundation, which houses this collection. While its focus is on Nijinsky and the Ballets Russes era (an entire wall is covered with framed drawings of Sergei Diaghilev, the Ballets Russes impresario), the collection encompasses the entire world of dance. Thousands of books, photographs, stage designs, etchings, lithographs, programs, letters and porcelain figures are all meticulously displayed and cataloged. (Neumeier said the foundation has plans to move into another building that will be accessible to the public, financed through his royalties and fundraising.)

Speaking in one of the book-lined rooms, Neumeier said that he knew early on that he wanted to choreograph. To please his parents, he studied English literature and theater at the Jesuit-run Marquette University in Milwaukee, but commuted to Chicago three days a week to take ballet classes, and performed with Shearer’s modern company for two years.

In 1962, he moved to Europe, joining the Stuttgart Ballet in Germany in 1963. There, encouraged by the director, John Cranko, he started to create ballets. At 30, he became the director of the Frankfurt Ballet. “I thought, choreography is what I want to do,” he said. “Better to start young than old.”

Three years later, in 1973, the invitation came from Hamburg. “I wasn’t convinced,” Neumeier said. “I was interested in forming an ensemble structured like a theater group, not a hierarchical ballet company. But I wanted a bigger canvas, a bigger company, pointe shoes for the ladies, to explore the full-length ballet structure. I decided to take the leap.”

Over his long career, Neumeier has produced story ballets based on literary texts (“Lady of the Camellias,” “A Streetcar Named Desire,” “Othello”) and other sources (“Nijinsky,” unsurprisingly); his own versions of ballet classics (“Romeo and Juliet,” “Nutcracker,” “Swan Lake”); abstract pieces centered on biblical subjects; and symphonic ballets, including seven set to Mahler.

“Of course he has done many big classical works, but his priority is very modern,” said Kevin Haigen, the company’s principal ballet master and the director of the National Youth Ballet, which Neumeier established in 2011. “That’s why he reveres Nijinsky. The older I get, the more I realize the influence of Sybil Shearer. It’s essential to him that the emotion builds the movement, that ballet is not just aesthetic, but human.”

Alessandra Ferri, on whom Neumeier created “Duse” in 2015, said that she sees Neumeier as “the continuation of a lineage, from Ashton, MacMillan, Robbins, Tudor, de Mille.”

“I learned with him a craft,” she added, “about theatricality, how everything matters, nothing is casual. It’s like working with a stage director, not just a choreographer.”

From the outset, Neumeier said, his goal was “to create a feeling that we are all working equally together.” An opera company, he added, is “like an expensive florist. If you can pay for a flower, you can get it. A ballet company is like a garden that grows over time.”

Ballerina Alina Cojocaru, who will appear at the Nijinsky gala, said that working with Neumeier, whether on an existing role or a new one, “feels like he is creating it for you in the moment.”

The feedback, Cojocaru said, “is personal, honest, intimate, and there is no right or wrong: It’s about the emotion, not the steps.” Every member of the company, she added, “has the same commitment as a principal dancer.”

For Volpi, poised to take over a company that is almost entirely identified with one man, his ethic and aesthetic, the stakes are high.

“There is no handbook for this one,” Volpi, 38, said in an interview in Düsseldorf, at the rehearsal studios of the Ballet am Rhein, which he has directed since 2020.

Volpi, who, at 4, began studying ballet in Buenos Aires with Nancy Bocca, the mother of star dancer Julio Bocca, began choreographing in 2006 “as a learning experience,” a few years after joining the Stuttgart Ballet. In 2013, he was appointed resident choreographer there after the success of the full-length “Krabat.” When that job ended, in 2017, he moved to Berlin “for a change” and quickly got the call from Düsseldorf. “I never finished unpacking,” he said.

The call asking him to apply for the Hamburg position was even more surprising, he said. “But how could I not explore it?” In Germany, he added, “directors often feel they must move on and change things. But ballet companies are people, not an abstraction, and John is alive. This was the most interesting part: To be in dialogue with the past and the present.”

Volpi, who speaks fluent English with easy charm, said that while “the core DNA of the company will always remain John’s work” and narrative ballets, he would like to expose the company to a variety of choreographic languages. (Non-Neumeier works only make up about 15% of the repertoire.) “I think it’s also important to give the audience other ways of looking at ballet,” he said.

Spuck, who worked with Volpi at the Stuttgart Ballet, said he thought Volpi was up to the challenges. “Demis Volpi is a super networker,” Spuck said. “He knows everybody, he is able to take responsibility and engage with people outside the dance world, and is a real leader.”

Neumeier, who had no part in Volpi’s selection, said he was “positive” about the choice, but had no right to legislate about the preservation of his legacy. “It’s more the sense of creativity that is important for me,” he said, “that it’s not just another company with the most popular classical or contemporary works of the moment.”

What will he do next? “Become a freelance choreographer!” he said, adding that he has around 10 projects planned for next year. He has also signed a seven-year contract to run an annual festival that the German town Baden-Baden has created in his name, and is planning an American-themed edition next year.

John Neumeier is sticking around.

This article originally appeared in The New York Times.