Christians retroactively placed Muslims at the Crucifixion centuries before Islam existed

Evidence

For Christians, evil was a reality—the cause of illnesses, wars, and calamities—often personified in Satan, demons, and monsters. Satan was a character that dwelled among men. Demons as well occupied numerous spaces in the medieval imagination. According to Origen, the Antichrist forced humans to act out of accordance with God’s rules through “evil daimones and evil angels.” Jews and Muslims were linked to these acts, and eventually, Muslims were placed at the Crucifixion and other pre-Islamic crimes. — Sophia Rose Arjana, Muslims in the Western Imagination, 93

Categorization

• FICTION: The idea of retroactive placement of a people at a historical crime they could not have committed is a powerful anachronism device for speculative fiction.
• QUESTION: What theological mechanism allowed Christians to blame Muslims for pre-Islamic crimes like the Crucifixion? Worth tracing the exegetical steps.