What Were They Thinking?
When the Madonna of the Veil came to light in 1930, the art world celebrated it as a newly discovered work of Botticelli. But doubts began to creep in four years later when Kenneth Clark, director of the National Gallery, noticed something suspicious about the Renaissance masterpiece. Subsequent tests of the paint revealed it was a forgery, but the big tip-off was that the Madonna looked like a silent movie star. Jean Harlow, to be specific.
Every era has its blind spots - things that people simply cannot see at the time that become obvious a few years later. The forger who created the Madonna didn't intend her to look like Jean Harlow. That was just how women looked in his day. If you're writing historical fiction, recognizing and reproducing these blind spots can make your readers feel like they are truly immersed in the era you're recreating.
One reason Alan Gordon's Fool's Guild mysteries work so well is that his characters inhabit the early thirteenth century. If you're not familiar with the series, it involves members of a jester's guild who work behind the scenes to manipulate nations toward a gentler, more humane government. Jesters, after all, can say anything to the king without fear of being beheaded (well, without much fear). One of the authentic details Gordon recreates is that everyone assumes the way to create the best government is to make sure the right man winds up as king. Someone has to have absolute power, because how else are you going to govern a nation?
Obsessions are another form of blind spot. One way Peter Tremayne creates the seventh-century atmosphere of the Sister Fidelma mysteries is through the frequent arguments over arcane religious customs, like how to calculate the correct date of Easter. Everyone agreed that Easter was the first Sunday after the full moon that follows the vernal equinox. The disagreement was over whether a day began at sunrise or sunset, and your answer could lead to you celebrating the holiday five weeks earlier or later than your fellow believers. Granted, there was also some politics involved in the question, but it's still hard not to look back now and say, "Just flip a coin, guys."
Of course, it's possible to go overboard in showing your historical characters' obsessions. Sixteenth-century England was pretty wrought up over the threat of hellfire and brimstone, but watching characters fret about whether or not they're among the elect can wear after a while. One way around this is to have your main characters be a bit out of the mainstream of their culture. Not that they should think there's something wrong with their culture's obsessions. If they think about it at all, they should feel that the problem is with them.
Hillary Mantel's Wolf Hall contains plenty of relics and references to hellfire. But her Thomas Cromwell, through whose eyes we see the entire story, is so damaged by his own past and so full of ambition that he doesn't have the leisure to dread damnation. When he attacks the Catholic Church, it's not to save souls. It's to move the fortune under its care to the coffers of Henry VIII.
Remember, too, that you can use the blind spots and obsessions to recreate more than history. They also define eras from the recent past. One reason Lauren Groff's Arcadia is such a pleasure to read is that her characters recreate the idealistic, heady mindset of the back to the land communal movement of the early seventies. No personal possessions, a vegan lifestyle, open marriages, communal leadership - what could go wrong? Groff makes it real with hungry children and third world sanitation arrangements.
So how do you uncover the tacit assumptions and outright obsessions of the era you're writing about? Read bad books. Great books are timeless, appealing to the underlying humanity of every era. Mediocre books - forgotten theological tracts, hack novels, uninspired plays -- publish because they speak to their age. They reflect the sorts of things ordinary people cared most - and least - about. The best mediocre books are the ones that were widely popular when they were first published and have now been forgotten - Bulwer-Lytton is a wonderful window into the thinking of the Victorian age. And thanks to the miracle of the internet, a lot of these books are now at your fingertips, often for free.
One final warning - our ancestors were not stupid. The obsessions and blind spots that define an era were held by intelligent, sensitive people. So treat your characters with respect, even when they're doing things that make your readers wonder, "What were they thinking?" Remember, in just a few years, people will be asking the same question about us.