In 2014, the PBS series NOVA aired an episode called "Ghosts of Murdered Kings." The show discusses corpses that have been found buried in peat bogs in northern Europe. Careful study demonstrates that the bodies are of high-status individuals, possibly local kings, who were intentionally killed. Not only were they killed, they were subjected to several different kinds of fatal attack. One might have been drowned, then hung, then severely stabbed. That style of multiple death is called "overkill."
The evidence suggests that these kings were culturally Celtic. In that culture, if there was a serious failure of crops the king was taken to the local fertility goddess's sacred spot (possibly in a bog) and was overkilled to appease her.
That NOVA episode could have been written by James Frazer for his 1890s book, The Golden Bough. His work, which eventually stretched to 12 volumes in the third edition, was all about a local person being designated as the representative of a fertility god, and that person being sacrificed as the god died, in order for the god to be born again to allow the crops to return. Frazer was very influential in the early 20th century, among writers such as T.S. Eliot and James Joyce.
The URL to the NOVA epidsode is: http://www.pbs.org/wgbh/nova/ancient/ghosts-murdered-kings.html
This relates to Confederacy because one theory of Carnival is that it is derived from Saturnalia, a Roman festival with some similarities to these Celtic rites. In Saturnalia, a Lord of Misrule, a representative of the god Saturn, was killed to restore the fertility of the land. Ignatius in Confederacy can be seen as a scapegoated Lord of Misrule. His almost being killed by the streetcar is a type of mock death.