The National Ballet was formed in 1963 through the amalgamation of Joan Denise Moriarty's Irish Theatre Ballet and the National Ballet Company directed by Patricia Ryan. Moriarty and Ryan were appointed co-directors of the company, but the two women and their visions for ballet were radically different, and the company disbanded in 1964, shortly after its first season.
Founded in 1950 by Alicia Markova and Anton Dolin under the name Gala Performances of Ballet. It was later renamed, Festival Ballet, then London Festival Ballet, and finally, in June 1989, English National Ballet, under which name it continues to operate.
Irish Theatre Ballet was founded by Joan Denise Moriarty in 1959 with Marie Rambert as its patron. The company's first performance took place in December 1959. The company received modest funding from the Arts Council, but depended heavily on private sponsors for its survival. In 1963, to resolve the company's financial problems, the Arts Council insisted on its amalgamation with Patricia Ryan's National Ballet Company in Dublin.