How did Shakespeare do it? How did the author of King Lear, Henry IV, Part One, and The Winter’s Tale compose two plays a year for almost two decades? A comparative look at the writing of Coriolanus may provide a glimpse into his creative process.

We have no posed snapshots of the Bard at his desk, pen in hand, the muse gleaming in his upturned eyes. We don’t even know which hand he used, but envision permanent ink splotches on the one that held the feathered quill.

He probably wrote at night, since he worked at the theater until sundown. And legend has it he wrote at blazing speed, so fast that he rarely bothered with commas. “His mind and hand went together,” said the editors of the First Folio, “and what he thought he uttered with the easiness that we have scarce received from him a blot in his papers” — to which his rival, Ben Jonson, who advocated a slower compositional pace, replied, “would he had blotted a thousand.”

Shakespeare probably read at night as well. Charles Nicholl, in The Lodger Shakespeare, says he was a “voracious, though probably — like most creative writers — an opportunist reader. He read for what he needed as often as for pleasure.”

For Coriolanus, Shakespeare used Plutarch’s Parallel Lives of the Greeks and Romans, translated by Sir Thomas North (from Jacques Amyot’s French version) in 1579. Shakespeare probably consulted the revised, 1595 edition, which meant he needed more than a cramped writing desk to accommodate its foot-tall pile of folio pages.

Valiant, with a “haughty and fierce mind,” Caius Martius Corolanus was a Roman around 500 BCE, when the city was one among many, all unconnected, in Italy. Fatherless, raised by a domineering mother, he was an absolute elitist, with bottomless ambitions, who detested the masses.

North/Plutarch writes: “For he was a man too full of passion and choler, and too much given over to self-will and opinion, as one of a high mind and great courage, that lacked the gravity and affability that is gotten with judgment of learning and reason.”

Plutarch attributes Coriolanus’s behavior to a lack of education, which made him “churlish, uncivil, and altogether unfit for any man’s conversation.” Shakespeare downplays education as a cause, but stresses the intemperance. He also adds that Coriolanus can’t “dissemble” — can’t be other than himself. At war he’s Achilles. At home, he’s miscast on a political stage, jammed with actors feigning roles.

North: In his first battle, age 16, “Martius valiantly fought in the sight of the Dictator [Tarquin]; and a Roman soldier being thrown to the ground, Martius straight bestrid him and slew the enemy with his own hands that had overthrown the Roman.”

Shakespeare activates the scene: “With his Amazonian chin he drove/The bristled lips before him; he bestrid the o’er-press’d Roman and in [Tarquin’s] view/Slew three opposers.”

Sixteen battles later, at Corioli, southwest of Rome, Caius Martius earns his “extra name.” According to Plutarch, as his soldiers ran away, Coriolanus fought through the gates and into the city with a handful of others.

As before, Shakespeare ups the valor count. Coriolanus orders his soldiers — “you souls of geese that beat the shapes of men” — to follow him. But none do. So he makes his charge alone. He returns, red as a “carbuncle,” and the Romans storm the city. For his courage, Caius Martius becomes “Coriolanus,” named for the victory he won.

North explains: “The first name the Romans have, as Caius, was our Christian name now. The second, as Martius, was the name of the house and family they came of. The third was some addition given, either for some act of notable service, or for some mark on their face, or some shape of their body, or else for some special virtue they had.”

Obsessed with what is and is not dramatic, Shakespeare omits the nomenclature seminar: “For what he hath did before Corioli, call him/With all the applause and clamor of the host,/Caius Martius Coriolanus! Bear/The addition nobly ever!”

Soon after the battle, the Romans sack Corioli. Plutarch: “The most part of the soldiers began incontinently to spoil, to carry away, and to lock up the booty they had won. But [Coriolanus] was angry with them.”

Shakespeare riffs the scene: “See here,” says Coriolanus, “these movers that do prize their hours/At a crack’d drachma! Cushions, leaden spoons/Irons of a doit, doublets that hangmen would/Bury with those that wore them, these base slaves/Ere the fight be done, pack up: down with them!”

Speeches like this, which paint a vivid portrait with charged particulars — and with scant help from the drab original — make one wonder how much acting Shakespeare’s company actually did. Although his plays abound with theatricality, Shakespeare always writes as if his audience wore blindfolds.

Plutarch: “Martius...did somewhat sharply take up those who went about to gratify the people, and called them people-pleasers and traitors to the nobility...they nourished against themselves the naughty seed and cockle of insolency and sedition which had been sowed and scattered abroad amongst the people.”

Shakespeare: “In soothing them, we nourish ‘gainst our Senate/The cockle of rebellion, insolence, sedition,/Which we ourselves have plough’d for, sow’d/And scattered.”

We need to cut the Bard some slack here. The Jacobean Age had few copyright laws. So Shakespeare borrowed, often word for word, from his sources. He had to. His company, the King’s Men, expected two scripts a year. Break that down: a five-act play every six months; so an act a month, with one off for good behavior, while working a day job. A borrower he had to be. By contrast, today’s playwrights write one every two, or even three years.

But the words Shakespeare keeps, like “cockle,” pass his sharpness test. In effect, he borrows from North when North sounds most Shakespearean.

Working from sources offered a distinct advantage: Shakespeare always knew where he was going. He could block scenes in advance and could concentrate on the journey — making local discoveries along the way — and not the destination.

Ben Jonson preferred stately, measured cadences. Between 1601 and 1607, Shakespeare’s verbal choices take on a restless, even frenetic quality. He knows how to unearth them and seems driven to mine deeper linguistic veins. By the time he wrote Coriolanus, around 1607, he had written over 30 plays. He pulls back some, trims his style — almost, but not quite, to a Jonsonian degree — and makes his source carry much of the load.

Caroline Spurgeon, one of his most insightful commentators, says that when Shakespeare wrote with his “imagination at white heat,” his dominating images often sprang uncoaxed from his unconscious. A subject triggered surprises, especially when he was riffing. Like well-trained Stratford grammar-schoolers, he begins a speech with a topic sentence; then he ad libs for several lines, sometimes with excessive verbiage — Jonson did have a point — but often with brilliance.

Although penned at less than “white hot” speed, Coriolanus has a touch that must have come from deep within. After the victory that gave him his name, Coriolanus asks a favor of the Consul Cominius. A wealthy old Volscian friend has been taken prisoner. North: “It would do me great pleasure if I could save him from this one danger, to keep him from being a slave.” When his comrades hear this sentiment — one of the few he displays — they praise Coriolanus all the more, and the man goes free.

Shakespeare makes two changes. The wealthy friend becomes a poor man. When Cominius assents to the request, he asks the man’s name, Coriolanus stops, responds: “By Jupiter! forgot!/I am weary; yea, my memory is tired./Have you no wine here?” And they stroll off-stage.

How he performed this alchemy, how he stored and tapped into his inner lexicon — and kept his inner editor muzzled — are what made him Shakespeare.