Say it Over a Few Times

This is surely one of the most recitable passages in the history of language:

"Deh, quando tu sarai tornato al mondo,
e riposato de la lunga via",
seguitò 'l terzo spirito al secondo,
"Ricorditi di me, che son la Pia;
Siena mi fé, disfecemi Maremma:
salsi colui che 'nnanellata pria
disposando m'avea con la sua gemma."

That's Dante, Purgatorio V, 130ff. Wiki offers:

Ah, when you have returned to the world,
and rested from the long journey,"
followed the third spirit after the second,
"remember me, the one who is Pia;
Siena made me, Maremma undid me:
he knows it, the one who first encircled
my finger with his jewel, when he married me

Eric Auerbach elaborates:
Here no motivation or detail is given;

Dante's contemporaries may well have filled out the allusion, but we ourselves have no definite information about Pia de' Tolomei. Yet nothing seems lacking; she is entirely real and distinct. Her memory is wholly concentrated on the hour of her death, which sealed her final fate; in that memory and in her supplication to remember her on earth, the whole of her being unfolds; and the on line that is not concerned with herself, her sweet and tender words to Dante--e risposato de la lunga via"--tells us all we need to know of this woman in order to perceive her life in its full actualiity.

--Eric Auerbach, Dante: Poet of the Secular World 145 (NYRB ed. 2007).

The Wiki points to a Donizetti operatic version that I never heard of before. And here is a more academic discussion.