Final answer:
The author uses historical references to provide factual evidence for their arguments, to challenge conventional expectations in a rhetorically effective manner, and to offer a passage for further analysis and understanding of a subject or story.
Step-by-step explanation:
The author uses historical references in their narrative for a few key reasons. Firstly, such references can support the author's claims by providing factual evidence or by establishing a historical context that adds credibility to their point.
Secondly, mentioning significant events or figures from history can also challenge conventional expectations, showing the writer's intent to present their argument or story in a rhetorically effective way by either aligning with or opposing existing perspectives. Finally, historical references may serve as a passage for analysis, allowing readers to gain new insights into a subject by considering it within a larger, more established framework. This can also affect the interpretation of characters and events within a story, as shown in the sample passage that discusses how biblical imagery in Mary Shelley's 'Frankenstein' allows for deeper analysis of character motivations and authorial intent.