Theseus (/ˈθiːsiːəs/; Ancient Greek: Θησεύς [tʰɛːsěu̯s]) was the mythical king of Athens and was the son of Aethra by two fathers: Aegeus and Poseidon.

Theseus was a founder-hero, like Perseus, Cadmus, or Heracles (Hercules), all of whom battled and overcame foes that were identified with an archaic religious and social order. As Heracles was the Dorian hero, Theseus was a founding hero, considered by Athenians as their own great reformer: his name comes from the same root as θεσμός ("thesmos"), Greek for "The Gathering". The myths surrounding Theseus—his journeys, exploits, and family—have provided material for fiction throughout the ages.

Theseus was responsible for the synoikismos ("dwelling together")—the political unification of Attica under Athens, represented emblematically in his journey of labours, subduing ogres and monstrous beasts. Because he was the unifying king, Theseus built and occupied a palace on the fortress of the Acropolis that may have been similar to the palace that was excavated in Mycenae. Pausanias reports that after the synoikismos, Theseus established a cult of Aphrodite Pandemos ("Aphrodite of all the People") and Peitho on the southern slope of the Acropolis.

Teseo ("Theseus", HWV 9; Italian pronunciation: [teˈzɛo]) is an opera seria with music by George Frideric Handel, the only Handel opera that is in five acts. The Italian-language libretto was by Nicola Francesco Haym, after Philippe Quinault's Thésée. It was Handel's third London opera, intended to follow the success of Rinaldo after the unpopular Il pastor fido.

First performed on 10 January 1713,Teseo featured "magical" effects such as flying dragons, transformation scenes and apparitions and had a cast of notable Italian opera singers. It was a success with London audiences, receiving thirteen performances even though the stage machinery for the "magical" effects broke down, and would have received more performances had not one of the theatre's managers run away with the box office receipts.

Performance history

The opera was premiered at the Queen's Theatre in the Haymarket on 10 January 1713. It received an additional 12 performances through 16 May 1713. The singers included the castratos Valeriano Pellegrini and Valentino Urbani. Between 1713 and 1984, there were only two revivals, the first being the revival under Fritz Lehmann in Göttingen on 29 June 1947. As with all Baroque opera seria, Teseo went unperformed for many years, but with the revival of interest in Baroque music and historically informed musical performance since the 1960s,Teseo, like all Handel operas, receives performances at festivals and opera houses today. In 1985, the tercentenary of Handel's birth, the opera received three revivals. Among other productions, the Handel Festival, Halle performed the work in 2003,English Touring Opera produced Teseo in October and November 2007, and the Frankfurt Opera mounted a production in 2013.

Thésée (Theseus) is a tragédie en musique, an early type of French opera, in a prologue and five acts with music by Jean-Baptiste Lully and a libretto by Philippe Quinault based on Ovid's Metamorphoses. It was first performed on 11 January 1675 by the Paris Opera for the royal court at the Château de Saint-Germain-en-Laye and was first performed in public in April at the Théâtre du Palais-Royal in Paris.

The plot centres around a love triangle: Egée wants to marry his ward, princess Églé, while the sorceress Médée wishes to marry the young warrior Thésée, but Thésée and Églé love each other. Médée attempts to force the lovers to renounce each other: first by using her magic to bring Églé to a place of torment, then by convincing Egée to have Thésée killed as a potential threat to his reign. But before Thésée can drink the poison he has been given, Egée realises that Thésée is his lost son. He then gives Églé to Thésée. Médée takes vengeance by destroying the festive setting, but the goddess Minerve undoes this.