Jeanne d'Arc (Joan of Arc) was found guilty of heresy and burned at the stake at Rouen in 1431. Her story needs no retelling.
The first two verses of the song are from the standpoint of her executioner, Geoffrey Thérage, who was haunted by his part in her death - according to Pernoud, Thérage stated that he "greatly feared to be damned” for his part in the affair.
The third verse places this moral crisis in a more modern context.
Rachel Cory (Rachel Aliene Corrie) died in Rafah, Palestine in 2003 while taking part “in efforts to prevent the Israeli army's demolition of Palestinian houses” (quote from: https://en.wikipedia.org/wiki/Rachel_Corrie , 06 Feb 2017)