Short answers, pulled from the story.
The Phoenix and the Turtle was first published in 1601 as a supplement to Robert Chester's Love's Martyr, printed by Richard Field for the London bookseller Edward Blount. It did not appear in print again until 1640, when John Benson included it in a collected edition of Shakespeare's poems.
The Phoenix and the Turtle is a 67-line allegorical poem describing a funeral for the Phoenix and the Turtledove, who symbolise perfection and devoted love. The poem argues that their love created a perfect unity transcending logic, and it closes with a prayer for the two dead lovers who left no posterity.
Scholars have proposed several identifications. The most discussed are Sir John Salusbury and his wife Ursula Stanley, Queen Elizabeth I paired with either Salusbury or the Earl of Essex, and the Catholic martyr St. Anne Line with either her husband Roger Line or the priest Mark Barkworth. None of these readings has been universally accepted.
The poem has been called the first great published metaphysical poem because it uses the two birds to explore abstract ideas about love, identity, and unity. Its lines describing two beings sharing one essence, "Two distincts, division none", draw on philosophical and theological concepts linked to Renaissance Neoplatonism and the Christian doctrine of the Trinity.
Ben Jonson, George Chapman, and John Marston all contributed poems to the supplementary gathering appended to Chester's Love's Martyr in 1601. Two anonymous contributors, identified as Vatum Chorus and Ignoto, also appeared in the collection.
First proposed by Clara Longworth in the 1930s, the Catholic interpretation holds that the poem is a coded requiem for St. Anne Line, a Roman Catholic executed at Tyburn in 1601 and later canonised. Proponents point to the poem's advocacy of prayers for the dead and its parallels with the Dies Irae from the Catholic Liturgy for the Dead.