Mary Shelley included numerous literary references within her introductory comments to Frankenstein as well as in the novel itself. Most of these are listed in the Allusions feature of this guide. There are references to the plays Hamlet and Romeo and Juliet by William Shakespeare, Miguel de Cervantes’s novel Don Quixote, and multiple references to Samuel Taylor Coleridge’s epic poem The Rime of the Ancient Mariner. She also includes references to works by the same literary friends who were with her when she came up with the idea for Frankenstein, including Lord Byron’s 1812 narrative poem “Childe Harold’s Pilgrimage” and poems by her companion and soon-to-be-husband Percy Bysshe Shelley. However, most of these references, while clever, are not significant to her novel’s plot and ideas.

But there are three works Shelley references in Frankenstein that are more imporatant to understanding the novel, and in the case of one work—John Milton’s Paradise Lost—central to it. Each of these works is discussed below in the context of how they impact Frankenstein.

Paradise Lost (1667) by John Milton

The epic poem Paradise Lost is the masterwork of the renowned 17th-century English poet and political activist John Milton. It is referenced so often in Frankenstein—starting on the title page, where Mary Shelley placed an inscription from it (“Did I request thee, / Maker, from my clay / To mould me man? Did I solicit thee / From darkness to promote me?")—that it could almost be considered a companion work to the novel. Milton’s poem explores the biblical story of the fall of man, focusing primarily on the rebellion of Satan and the expulsion of Adam and Eve from the Garden of Eden. Amidst the cosmic struggle between God and Satan, the poem delves into themes of free will, disobedience, and the consequences of sin.

Shelley weaves in many of the 1667 poem’s plot elements and themes into her story, including the phrase “Angel of Destruction” (which Milton had used to describe Satan, the fallen archangel intent on destroying man, God’s new creation) in Chapter 3, and by having the monster compare his hut near the De Lacey family to “Pandæmonium” (the name of Satan’s grand kingdom in Hell in the poem) in Chapter 9. The novel’s tie-ins to Paradise Lost become stronger after the monster tells Victor in Chapter 15 that he read Milton’s poem while he and Victor were separated. While there is an inference that the monster doesn’t realize Paradise Lost is a work of fiction and not a historical account, the poem nevertheless has a huge impact on shaping his understanding of the world. In Chapter 15, he makes an extended comparison of himself to Satan as portrayed in the poem (like Satan, he is excluded from human life while envying its happiness and is rejected by his creator). This comparison comes full circle in the chapter called “Walton, in Continuation” when Victor compares himself to Milton’s Satan (saying that they were both overly ambitious) in one of his final self-reflections before dying.

Prometheus Bound (456 BCE) by Aeschylus

Prometheus Bound is a play by the ancient Greek tragedian Aeschylus that was likely written around 456 BCE. It tells the story of Prometheus, a Titan (the rulers of the universe before being overthrown by the Olympian gods) who defies the gods by giving fire to humanity and is subsequently punished for doing so by Zeus.

Shelley’s only explicit mention of the Prometheus legend is in the book’s subtitle. (Her full title for the novel is Frankenstein; or, The Modern Prometheus.) But the parallels between Prometheus and Victor Frankenstein are clear: both give away a treasured secret of the “gods” to humanity and both are severely punished for doing so. In Prometheus’s case, the treasure he divulges is fire, while for Frankenstein it is life itself. But for followers of the Romantic movement like Shelley, life and fire were essentially the same thing, as can be seen in an implicit reference to the Prometheus legend in a quote by Victor as he threatens to kill the monster in Chapter 10 (“You reproach me with your creation; come on, then, that I may extinguish the spark which I so negligently bestowed”). The “spark” Frankenstein threatens to extinguish symbolizes the monster’s life as well as fire, the gods’ secret that Prometheus gave to humankind, an act for which he was severely punished.

Another link between Shelley and the Prometheus legend is that her husband, the poet Percy Bysshe Shelley, wrote and published a Romantic play in 1820 called Prometheus Unbound. It explores another part of Prometheus’s story (which Aeschylus also wrote about in a play with the same title that is now lost) in which he escapes the gods’ torture and captivity through the power of the love he and his wife share.

The Sorrows of Young Werther (1774) by Johann Wolfgang von Goethe

The German author Goethe’s famous 1774 work, The Sorrows of Young Werther, which he revised and republished in 1787, tells the story of a young man whose love for a young woman named Charlotte is not reciprocated, leading him to suicide. The novel was hugely popular and was soon translated into several European languages. Its popularity led to a social phenomenon known as “Werther Fever” in which young European men would dress in the style of Werther as described in the book (boots, a yellow vest, and a blue jacket). An early and prime example of the Sturm und Drang (“storm and stress”) German literary movement, the novel was also a strong influence on writers in the later Romanic movement—including Mary Shelley.

The novel (identified as Sorrows of Werter) is one of the works that the monster tells Victor he has read in Chapter 15—along with Milton’s Paradise Lost and Plutarch’s Lives. Neither Plutarch’s work nor The Sorrows of Young Werther is mentioned again, but there is a clear connection between Frankenstein and Goethe’s novel: both are epistolary novels (works primarily constructed as a collection of letters or other documents). In Goethe’s novel, Werther tells his story mostly through letters to his best friend, Wilhelm. Frankenstein starts out with four letters from the shipboard explorer Robert Walton to his sister Margaret in London. Starting with Chapter 1, the story is being told in Frankenstein’s voice, and later we’ll hear the monster’s story (mostly as he told it to Victor). However, everything we learn is being conveyed within the context of Walton writing to his sister. The final chapter (“Walton, in Continuation”) is explicitly Walton’s fifth letter to Margaret, completing the epistolary structure loop.

Epistolary novels were popular at the time Frankenstein was written, and having the monster tell us he read The Sorrows of Young Werther is a huge tip-off that it probably inspired Shelley to use the format for her novel. The device fell out of favor in the years after Frankenstein was published, but it resurfaced later in the 19th century with novels such as Wilkie Collins’ The Moonstone (1868) and Bram Stoker’s horror classic Dracula (1897). In the late 20th century, the epistolary format became more popular than ever with well-known examples including Stephen King’s Carrie (1974), Alice Walker’s The Color Purple (1982), and The Perks of Being a Wallflower by Stephen Chbosky (1999).

The reason why the epistolary format might have appealed to Goethe, Shelley, and other authors who employed it might be because its direct first-person perspective allows authors to convey their stories in a more direct and less guarded manner that allows for increased authenticity and realism comparted to a more conventional structural approach.