Poor Mary Bennet. It’s hard not to feel her creator didn’t like her very much. Jane Austen described Pride and Prejudice as “light, bright and sparkling”; but she didn’t bestow any of these qualities on the unfortunate middle Bennet daughter. Unlike her sisters, Mary possesses neither looks, wit or charm. Her hard won “accomplishments” have only made her pompous and priggish. In a book in which even the characters we aren’t supposed to admire fizz and pop with energy – step forward Lydia Bennet – only Mary fails to shine.

So why choose her as the subject for a novel? On one level, I simply felt sorry for her. I’d been a bookish young woman myself, with all the usual misgivings about how I appeared to the world. I would have loved to be her elder sister Elizabeth – handsome, assured and funny. But in truth, I suspected there was more than a little of Mary about me.

But the same sympathy that drew me towards Mary made me reluctant to accept in its entirety Austen’s version of her. The qualities that condemn her in Pride and Prejudice did not seem so heinous to me. I thought her efforts to educate herself, in the face of her family’s indifference, commendable rather than ridiculous. And the earnestness that resulted from her lonely endeavours seemed rather sad and touching. The Mary I wanted to write about would look rather different from Austen’s character. But could readers ever be convinced to accept her? Once a character is established as fundamentally unlikable, can anything be done to make us change our minds?

Facebook Twitter Pinterest Giles Terera as Aaron Burr (in black suit) in the West End production of Hamilton. Photograph: Matthew Murphy

I’ve always believed that everything appears different if you can persuade readers to look at the world through that character’s eyes. Even the most unlikely figures can be redeemed. I’d seen this happen in one of the very first books I bought for myself, Rosemary Hawley Jarman’s We Speak No Treason. I was swept away by Jarman’s impassioned attempt to rescue Richard III from his dark status as one of the greatest villains in British history. I was thrilled by the idea that everything we thought we knew about Richard was wrong, that his character looked very different when viewed from the perspective of those who really knew him.

I developed a taste for similarly provocative fictional re-evaluations, and devoured Robert Graves’s I, Claudius, relishing the way in which the despised narrator is gradually revealed to be one of the cleverest and most cunning of the imperial Roman family. I returned again and again to Gore Vidal’s bracingly astringent Burr, which told the story of one of the most reviled figures of the American revolution. As the man who shot Alexander Hamilton, Aaron Burr is now probably as famous as he’s ever been, thanks to the musical Hamilton. However, he’s still seen as the bad guy – or baddish, at least.

This wouldn’t have worried Vidal very much, for unlike Jarman, it was never his intention to present the subject of his book as a hero. Jarman’s whole purpose was to clear Richard’s name, to present him as a victim of history. But for both Graves and Vidal, it was the moral ambiguity of their subjects that made them interesting. Their aim was not to whitewash them into goodness, but to enter into their hearts and minds and invite us to see the world from their bleakly pragmatic perspective. First we’re intrigued; then we’re immersed; and soon we find ourselves identifying with a character we’d previously thought irredeemable.

Facebook Twitter Pinterest Portrait of Sir Thomas Cromwell by Hans Holbein the Younger, 1532. Photograph: IanDagnall Computing/Alamy

For me, the greatest triumph of this genre is unquestionably Hilary Mantel’s Wolf Hall. After reading her seductive and nuanced picture of Thomas Cromwell it is impossible ever to think of him again just as Henry VIII’s cold, calculating enforcer, the man with the unsettling stare who gazes out of Holbein’s famous portrait. Mantel achieves this not by denying Cromwell’s dark side – he remains, in her telling, a man with a profoundly elastic moral compass – but by giving him a credible and complex inner life that, when fully appreciated, allows us to understand, if not always to condone, his actions. There is, she seems to suggest, no single Cromwell for us to pin down. Like all of us, he has a variety of guises in which he presents himself to the world. Some are ruthless, some more benign. What you think of him will very much depend on which of those faces you encounter.

It’s noticeable that all the central characters in these revisionist retellings are based on real people – and that all of them are men. This shouldn’t really surprise us. One of the purposes of these books is to make us think again about power and those who wield it. But there’s another form of fictional reimagining that has sought to sidestep these limitations by turning away from the heart of the action. It looks instead towards characters relegated to the margins and invites them into the spotlight.

Many of these new protagonists are drawn not from history but from familiar works of fiction – and many of them are women. A key example, and still one of the best, is Jean Rhys’s Wide Sargasso Sea. In Jane Eyre, the first Mrs Rochester, insane and hidden from view, cannot bear witness to her experiences; all we hear from her are cries and screams. But Rhys lets her speak – and having heard her story, it is impossible to think of her any longer as merely the malign impediment to Jane’s happy ending. We know now who Bertha Rochester is, and our feelings about her have shifted profoundly as a result.

Pat Barker’s The Silence of the Girls focuses on a different kind of voicelessness. Her book is loosely based on Homer’s Iliad, but is very much not a narrative of classical heroes. Instead it introduces us to the women who trudge along silently at the edge of the original, the mothers, wives and daughters who are the collateral damage of a war between men. Barker lifts them out of their anonymity, and in doing so transforms how we think of them.

Facebook Twitter Pinterest Victoria Sibson as Bertha Mason and Javier Torres as Edward Rochester in Northern Ballet’s Jane Eyre. Photograph: Caroline Holden

Alice Randall’s The Wind Done Gone explores the experience of a very different kind of dispossession. Taking its inspiration from Gone With the Wind, it turns away from the white-pillared plantation house and tells its story not from the perspective of the slave owners, but from the point of view of the enslaved. Randall’s characters don’t exist voicelessly in the background but stand full square before us. This turns an entire fictional landscape upside down, reshaping our sympathies in the process.

But if shifting perspective can make us feel more benign towards one character, it also alters how we see those around them. In Wolf Hall, the saintly Thomas More takes on a far darker quality. George Washington is a lumpish untrustworthy manipulator in Burr. In writing my own book, I too found established characters taking on a new identity. In Pride and Prejudice, Mary Bennet’s mother is selfish, tactless and annoying – but her power over its heroine is limited. Elizabeth is too confident to be seriously affected by her mother’s complaints. For Mary, however, who possesses none of the qualities her mother admires, Mrs Bennet is potentially a far more baleful presence, with the capacity to do real emotional damage. As we begin to identify more with Mary, we become less indulgent towards her mother.

Likability, in literature as in life, is a fluid and unpredictable quality. Even the greatest author can’t always control how a character is received. Fanny Price, the upright heroine of Mansfield Park, was one of Austen’s favourite characters; but although Fanny has her defenders, she’s never appealed to readers as much as she did to her creator. Fanny’s stern rectitude is worthy and deserving – but it doesn’t make her particularly sympathetic. In contrast, it’s impossible to dislike Mary Crawford, the novel’s bad girl. Yes, she’s self-absorbed and worldly, insufficiently respectful to the clergy, and takes far too light a view of adultery. But she’s also an irrepressible Austen character in her best “light, bright and sparkling” style. No matter that Mary has no principles, she wins our hearts nonetheless.

• The Other Bennet Sister by Janice Hadlow is published by Mantle. To order a copy go to guardianbookshop.com. Free UK p&p over £15.