On the first of September 1939, while Rassine was still a member of the Trois Arts company, German troops invaded Poland, whereupon the United Kingdom and France declared war on Germany, an event that was to have a dramatic effect on Rassine's burgeoning career. In late 1940, a group of Polish refugees formed the Anglo-Polish Ballet, specializing in Polish folk dances, and Rassine was invited to join. He soon became the leading classical dancer of the company, performing in
Michel Fokine's
Les Sylphides and
Le Spectre de la Rose with Natalia Rossowska. When
Ninette de Valois, director of the Sadler's Wells Ballet, came looking for male dancers to replace losses in her war-ravaged company, she was favorably impressed with Rassine but chose another dancer instead, the diminutive Gordon Hamilton, an Australian character dancer and mime. Subsequently, she had second thoughts and also offered Rassine a contract. In 1942, Rassine joined the Sadler's Wells Ballet, where he would remain until 1955. He was soon promoted to
premier danseur and was cast as partner to ballerinas
Nadia Nerina,
Pauline Clayden, and
Pamela May in
Giselle,
The Sleeping Beauty,
Coppélia, and other classic works. He was particularly noted for dancing the technically demanding role of the Bluebird in
The Sleeping Beauty. In the contemporary repertory, he created roles in a number of works by
Ninette de Valois,
Frederick Ashton, and
Robert Helpmann. He danced leading roles in many audience favorites: Harlequin in Fokine's
Carnaval, Vestris in de Valois's
The Prospect before Us, the Snob in
Léonide Massine's
La Boutique fantasque, and the Blue Boy in
Frederick Ashton's
Les Patineurs. His engaging personality made him well suited to lighthearted roles, but he was also adept at characterization in dramatic works. As a solo dancer, he was admired for his smooth, lithe movement, and he was valued by ballerinas such as
Margot Fonteyn,
Beryl Grey, and
Violetta Elvin as an exceptionally able partner. In 1958, he danced Albrecht to the Giselle of the great French ballerina
Yvette Chauviré in her guest appearances with the Royal Ballet. Rassine was also appreciated in his home country. He returned to Cape Town first in 1947, when he was invited to produce and dance in act two of
Giselle for the South African National Ballet, then under the direction of Cecily Robinson, with whom he had danced as a student in his youth. He subsequently formed an important partnership with his close friend
Nadia Nerina, a South African dancer who had become
prima ballerina at the Sadler's Wells Ballet. Together, they toured South Africa and
Southern Rhodesia (now
Zimbabwe) in 1952, presenting recital programs of
pas de deux and solo variations. They danced again in South Africa in 1955, appearing in
Giselle with the University of Cape Town Ballet. Although obliged to appear before whites-only audiences, because of the government policy of
apartheid, they were motivated by patriotism and a wish to contribute to the cultural life of the country. In later years, neither of them returned to live in their racially fragmented homeland. After the war in Europe ended in 1945, Rassine faced competition for roles in the Sadler's Wells repertory with the return of such excellent dancers as
Michael Somes,
Harold Turner, and
John Field, but he managed to hold his own until the early 1950s. By 1952, a new generation of male dancers, including the handsome and powerful
David Blair, had taken the spotlight on stage at
Covent Garden. Rassine was gradually relegated to second or third casts or was left out of new works altogether. By 1954, it was clear that his star had fallen from the Sadler's Wells firmament. He left the company in search of new opportunities, and he found them for a time as a guest with
Walter Gore's
London Ballet and companies abroad. Eventually, as he was almost forgotten by his former fans, he withdrew from the dance world and went into retirement. ==Roles created==