The Tale of Aragorn and Arwen

Mary Bowman compares the "feigned" historical echoing of Beren and Lúthien in the "Tale of Aragorn and Arwen" with Dante's echoing of Lancelot and Guinevere in his tale of Paolo and Francesca, here in an 1862 painting by Dante Gabriel Rossetti.

"'The Tale of Aragorn and Arwen' is a story within the Appendices of J. R. R. Tolkien's The Lord of the Rings. It narrates the love of the mortal Man Aragorn and the immortal Elf-maiden Arwen, telling the story of their first meeting, their eventual betrothal and marriage, and the circumstances of their deaths. Tolkien called the tale 'really essential to the story'. In contrast to the non-narrative appendices it extends the main story of the book to cover events both before and after it, one reason it would not fit in the main text. Tolkien gave another reason for its exclusion, namely that the main text is told from the hobbits' point of view. The tale to some extent mirrors the "Tale of Beren and Lúthien", set in an earlier age of Middle-earth. This creates a feeling of historical depth, in what scholars note is an approach similar to that of Dante in his Inferno. ..."

Wikipedia 

Going In Sorrow, But Not in Grief: Islam, Tolkien & Dying Well 

YouTube: The Love Story of Aragorn and Arwen

In Peter Jackson's The Lord of The Rings film trilogy, the tale is brought from the appendix into the main narrative, and (shown) Arwen brings the banner of the White Tree to Aragorn, and they are married. In the book these are separate events. Aragorn is shown wearing a circlet; Tolkien described the crown in the book as a taller version of the helmets of the city guard, and in a later letter as resembling the Hedjet of Upper Egypt