Question: What year did the Alliance Theatre stage its production of the semi-opera in five acts with music by Henry Purcell?

Context paragraphs:
Edward Henry Purcell: Edward Henry Purcell (died 1765), organist, printer, and music publisher, was the son of Edward Purcell, and grandson of the English Baroque master, Henry Purcell.  He was a chorister in the Chapel Royal in 1737.  Upon the death of his father in 1740, he succeeded him as organist of St Clement, Eastcheap.

Mysteries of Yoshitsune I&amp;II: Moon Saga - Mysteries of Yoshitsune I&II is a theatre stage play written, composed and directed by Japanese recording artist Gackt.  The original soundtrack was released on October 1, 2014 and compiles music from the theatre stage play.  It consists of two music CDs for each chapter, the first of which was performed in 2012, while the second was performed in 2014.

Purcell Operatic Society: The Purcell Operatic Society was a short-lived but influential London opera company devoted to the production of stage works by Henry Purcell and his contemporaries.  It was founded in 1899 by the composer Martin Shaw and folded in 1902.  Its stage director and production designer was Gordon Craig whose productions for the company marked the beginning of his career as a theatre practitioner.  Their debut production of Purcell's opera "Dido and Aeneas" in 1900 was one of the earliest staged performances of the work in modern times.

Alliance Theatre: The Alliance Theatre is a theater company in Atlanta, Georgia, based at the Alliance Theatre, part of the Robert W. Woodruff Arts Center, and is the winner of the 2007 Regional Theatre Tony Award.  The company, originally the Atlanta Municipal Theatre, staged its first production ("King Arthur") at the Alliance in 1968.  The following year the company became the Alliance Theatre Company.

Semi-opera: The terms "semi-opera", "dramatic[k] opera" and "English opera" were all applied to Restoration entertainments that combined spoken plays with masque-like episodes employing singing and dancing characters.  They usually included machines in the manner of the restoration spectacular.  The first examples were the Shakespeare adaptations produced by Thomas Betterton with music by Matthew Locke.  After Locke's death a second flowering produced the semi-operas of Henry Purcell, notably "King Arthur" and "The Fairy-Queen".  Semi-opera received a deathblow when the Lord Chamberlain separately licensed plays without music and the new Italian opera.

Dioclesian: Dioclesian (The Prophetess: or, The History of Dioclesian) is a tragicomic semi-opera in five acts by Henry Purcell to a libretto by Thomas Betterton based on the play "The Prophetess", by John Fletcher and Philip Massinger, which in turn was based very loosely on the life of the Emperor Diocletian.  It was premiered in late May 1690 at the Queen's Theatre, Dorset Garden.  The play was first produced in 1622.  [??]  Choreography for the various dances was provided by Josias Priest, who worked with Purcell on several other semi-operas.

The Indian Queen (opera): The Indian Queen (Z. 630) is a largely unfinished semi-opera with music by Henry Purcell, first performed at the Theatre Royal, Drury Lane, London, in 1695.  The exact date is unknown, but Peter Holman surmises it may have been in June.

The Fairy-Queen: The Fairy-Queen (1692; Purcell catalogue number Z.629) is a masque or semi-opera by Henry Purcell; a "Restoration spectacular".  The libretto is an anonymous adaptation of William Shakespeare's wedding comedy "A Midsummer Night's Dream".  First performed in 1692, "The Fairy-Queen" was composed three years before Purcell's death at the age of 35.  Following his death, the score was lost and only rediscovered early in the twentieth century.

King Arthur (opera): King Arthur, or The British Worthy (Z. 628), is a semi-opera in five acts with music by Henry Purcell and a

Bethany Anne Lind: Bethany Anne Lind is an American stage and screen actor in Atlanta, Georgia and New York City, New York.  She is best known for creating roles in world premieres such as Margo in "Carapace"" (at Alliance Theatre), Olivia in "26 Miles" (at Alliance Theatre), and Dora in "The Storytelling Ability of a Boy" (at Florida Stage).

Supporting paragraphs: Alliance Theatre King Arthur (opera)
Answer: 1968