Union Jack was created to honor the British heritage of the United States on the occasion of its Bicentennial.

Part I is based on Scottish military tattoos and folk-dance forms performed in an open castle square. Part II is a music-hall pas de deux for the costermonger Pearly King and Queen of London, with two little girls and a donkey, danced before a drop suggesting Pollock's toy theaters. Part III is a series of variations employing hornpipes, sea songs, work chants, jigs, and drill orders of the Royal Navy, in a dockside setting. For the finale, hand flags signal 'God Save the Queen' in semaphore code as the Union Jack unfurls. Hershy Kay (1919-1981) established himself as a preeminent orchestrator of musicals with Leonard Bernstein's On The Town in 1944. His works for the ballet include Cakewalk, Clowns, Western Symphony, Stars and Stripes, Who Cares?, and Union Jack; his works for the musical theater include Peter Pan, Once Upon a Mattress, Candide, A Chorus Line, Evita and Barnum. A composer in his own right, Hershy Kay also reconstructed Louis Moreau Gottschalk's Grande Tarantelle for Piano and Orchestra, which later became the Balanchine ballet Tarantella. Mr. Kay's work also includes a children's record, Mother Goose.

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