The names of the Roman months were Januarius, Februarius, Martius, Aprilis, Maius, Junius, Julius (to honor Julius Caesar), Augustus (to honor Caesar Augustus), September, October, November, and December.

The first day of each month was called the Kalends. The Ides fell on the fifteenth day of Martius, Maius, Julius, and October, and on the thirteenth day of the other months. The Nones fell nine days before the Ides. The Romans reckoned dates by counting backward, inclusively, from the Kalends, Ides, or Nones. Thus, for example, the date we would call June 9 was called by the Romans the fifth day before the Ides of Junius.

Lucius woke with a start.

He had been dreaming. In his dream there was no earth, only a dark, empty sky, and beyond the sky, unimaginably vast, the crystalline firmament in which the stars shone brightly. No clouds obscured the stars, and yet there was lightning in the dream, lightning without thunder, random flashes of blinding light that illuminated great flocks of birds that suddenly filled the dark sky. There were vultures and eagles, ravens and crows, every sort of bird imaginable, soaring and flapping their wings, yet making no more sound than the silent lightning. The dream had filled him with a sense of urgency and confusion.

Awake now, Lucius heard a faint rumble of thunder in the distance.

He heard other sounds from elsewhere in the house. The slaves were up and beginning to stir, stoking the kitchen fire and opening shutters.

Lucius jumped from his bed. His room, with a small balcony looking west, was on the upper floor of the house. Below him was the slope of the Aventine Hill. The nearer houses, along the crest of the hill, were large and well made, like his family’s house. Farther down the hill, humbler houses and tenements and artisans’ workshops were crowded close together, and farther yet was a flat expanse with large granaries and warehouses close to the Tiber. At the river the city ended. On the far side of the Tiber, woods and meadows were divided into the private estates of the rich, which extended to the far horizon of hills and mountains.

How his mother hated this view! Born into a wealthy branch of the Cornelius family, she had grown up in a house on the other, more fashionable side of the Aventine Hill, with a view of the vast Circus Maximus below, the Capitoline Hill crowned by temples off to one side, and, directly opposite, the opulent Palatine Hill, where the emperor lived. “Why, from our rooftop, when I was a girl,” she would say, “I could see the smoke from sacrifices on the Capitoline, watch the chariot races below, and even catch a glimpse of the emperor himself, strolling on one of his terraces across the way.” (“All at the same time, Camilla?” Lucius’s father would say, gently mocking her.) But this was the view Lucius had grown up with. For twenty-four years this had been the Roma seen from his room, a jumble of the rich and poor – mostly the poor – where slaves laboured endlessly in vast storehouses to accommodate all the goods and grain that arrived day after day, carried up the river from the great world beyond, the world that belonged to Roma.

The month of Maius had been overcast and rainy so far, and this day promised to be no different. By the dim light of dawn beneath an overcast sky, Lucius saw the towering cypress trees along the Tiber sway this way and that. The blustering winds were warm and carried the smell of rain. In the far distance, black storm clouds roiled on the horizon, bristling with lighting.

“Perfect weather for an augury!” whispered Lucius.

His room was sparsely furnished with a narrow bed and a single backless chair, a small pigeonhole bookcase filled with scrolls left over from his childhood education, a mirror on a stand made of burnished copper, and a few trunks to accommodate his clothing. He opened the most ornate of the trunks and carefully removed the special garment it contained.

Ordinarily, he would have waited for a slave to help him dress – arranging the folds correctly was a complicated task – but Lucius could not wait. The garment was not simply a toga, such as the one he had put on when he became a man at the age of seventeen. It was a trabea, the special garment worn only by augurs, the members of the ancient priesthood trained to divine the will of the gods. It was not white but saffron with broad purple stripes. Except for the fitting, when the tailor had made it for him, this was the first time Lucius had even touched the trabea. The never-worn wool was soft and thick and had a fresh smell of murex dye.

He put on the garment and did his best to pull the hanging folds into a proper arrangement. He glanced at himself in the copper mirror, then reached into the trunk again. He picked up a slender ivory wand that ended in a little spiral. The lituus was a family heirloom and a familiar friend; Lucius had spent countless hours practising with it in preparation for this day. But now he looked at the lituus with fresh eyes, studying the intricate carvings that decorated every part of its surface with images of ravens, crows, owls, eagles, vultures and chickens, as well as foxes, wolves, horses and dogs – all the various creatures from whose actions a trained augur could interpret the will of the gods.

He left his room and descended the stairs, crossed the garden surrounded by a peristyle at the centre of the house, and stepped into the dining room, where his mother and father reclined together on a couch while a slave served their breakfast.

His mother was wearing a simple stola, with her long hair not yet combed and pinned for the day. She leaped up from her couch. “Lucius! What are you doing dressed in your trabea already? You can’t eat breakfast wearing that! What if you get food on it? The ceremony is hours away. We’ll be going to the baths first. The barber must shave you and your father-”

Lucius laughed. “Mother, I did it on a whim. Of course I won’t wear it to breakfast. But what do you think?”

Camilla sighed. “You look splendid, Lucius. Absolutely splendid! As handsome as ever your father was in his trabea. Don’t you think so, dear?”

Lucius’s father, who strove always to maintain the restraint proper to a man of his standing – a patrician, a senator, and a cousin of the emperor – merely nodded. “Handsome our boy certainly is. But looking pretty is not the point when a man puts on his trabea. A priest must carry his garment as he carries his lituus, with dignity and authority, as befits the intermediary of the gods.”

Lucius drew back his shoulders, raised his chin, and held forth his lituus. “What do you think, father? Do I look properly dignified?”

The elder Lucius Pinarius looked at his son and raised an eyebrow. To him, young Lucius often still looked like a boy, and never more so than at this moment, dressed up in priestly finery but with the folds of his trabea tucked and draped haphazardly, like a child in grown-up costume. Twenty-four was very young for a man to be inducted into the college of augurs. The elder Pinarius had been in his forties before the honour came to him. With his black hair mussed from sleeping, his broad smile, and his smoothly handsome features, young Lucius hardly fitted the standard image of the wrinkled, grey-haired augur. Still, the young man came from a long line of augurs, and he had shown great aptitude in his studies.