Mary Shelley is primarily known for writing Frankenstein (1818), and while many people think themselves familiar with the tale, their knowledge is usually based on the many play and film adaptations, rather than the original literary text. In the Billion Year Spree: The History Of Science Fiction (1973), Brian Aldiss argued quite successfully that Frankenstein is the first science fiction novel. Certainly the creation of a manufactured being, based to some extent on the science of the day should qualify as such. How then should we examine Shelley's later novel, The Last Man (1826)? While I don't believe that it really qualifies as science fiction, many of the themes Shelley includes are familiar to a modern audience. This post apocalyptic tale will seem familiar to readers of modern anthologies such as Wastelands, edited by John Joseph Adams. Stories like The Last Man bear a strong similarity to works by Stephen King, such as The Stand (1978), where a global catastrophe has depopulated the earth. Unlike King's novel, Mary Shelley's story lacks the supernatural elements, aside from the narrative framing device. Shelley mourns for a lost world, just as she mourned for her husband and child. As she notes in her novel, "all things proceed, decay, and perish".
Much of her novel can be seen as semi-autobiographical. Many of the characters seem based off those in her life. The story is a kind of momento mori, memorializing those who proceeded her. In many ways, The Last Man deals with death and emotion in a far more sophisticated way than Shelley dealt with this issue in Frankenstein. While Victor Frankenstein is unable to express grief or true remorse for anyone, in The Last Man, Lionel Verney memorializes the entire world, saying that "my thoughts were gems to enrich the treasure house of man's intellectual possessions; each sentiment was a precious gift I bestowed on them". Verney becomes a kind of living monument to the peoples of the earth.
This theme can also be seen in Richard Matheson's novel, I Am Legend (1954), for which the movie adaptation starring Will Smith utterly fails to conclude in a satisfying manner. In Matheson's novel, Neville is also a "last man", fighting for the memory of mankind.
While Shelley's The Last Man may not fully qualify as science fiction, the themes she used have formed a groundwork for authors who have worked inside and outside the genre ever since.