What does the poem "Richard" by Carol Ann Duffy have to do with the play Richard III? What ideas can be drawn from the poem?

"Richard" is a 2015 poem written by Scottish poet laureate Carol Ann Duffy, in honor of one of Britain’s most well-known kings—Richard III. The king’s bones were found 500 years after his death at the Battle of Bosworth Field in 1485, under a parking lot in Leicester, England. The poem describes the king’s honorary reburial, hinting at how he never got his dignified funeral, as he was originally hastily buried by the monks who found his body.
The poem is narrated by Richard himself and focuses on the “description of his soul.” Duffy shows him as a melancholic, almost poetic man who talks about his deep state of mind, his emotional turmoil, his pride, and even his faith. Duffy writes of religious symbols, votives, and life after death, which might allude to Christianity. At one point, Richard says, “the symbol severed from me when I died,” which is a reference to the cross that was taken away from him when he died. As you can see, Richard speaks in a very direct manner, as if he were still alive.
This is in direct contrast to Shakespeare’s Richard, who is portrayed as a mysterious, enigmatic, nefarious, and clever villain. Unlike Duffy, who focuses on Richard’s inner thoughts and feelings, Shakespeare creates and develops Richard’s character by focusing on his political, moral, and ethical views and opinions. In fact, the only time that Shakespeare portrays Richard III as a good, just, brave, and capable leader is on the battlefield. Basically, Shakespeare directly blames Richard for the fall of the kingdom, while Duffy attempts to humanize his character, giving him a voice.
Thus, Duffy’s Richard comes the closest to Shakespeare’s Richard in one particular scene: the night before the Bosworth battle, when the king is visited by the spirits of all the victims that died or suffered at his hands or his orders. In the play, Richard begins to question his conscience, perhaps showing remorse about his wrongdoings and regrets that he will be remembered as a villain.

My conscience hath a thousand several tongues,And every tongue brings in a several tale,And every tale condemns me for a villain.

This sad, almost elegiac tone is heavily reminiscent of Duffy’s poem, in which Richard tells us of his dreams where the people pray for his soul:

or I once dreamed of this, your future breathin prayer for me, lost long, forever found;or sensed you from the backstage of my death,as kings glimpse shadows on a battleground.