The heroine of my debut novel, Lily of the Nile, is Cleopatra’s daughter, the young Princess of Egypt who would be marched as a chained prisoner through the streets of Rome. At the end of a Roman triumph–that military parade during which generals celebrated their victories–their captives were often strangled or killed. There were, however, notable exceptions.

The children of royal families were sometimes spared from execution and kept as hostages to secure the submission of any remaining allies and ensure the good behavior of their conquered homelands. Such was the case with Cleopatra Selene, her twin Alexander Helios, and their younger brother Ptolemy Philadelphus. These three young children, the last survivors of the Ptolemaic dynasty, were not only spared, but taken into the household of Augustus to be reared by his sister.

Though hostage-taking was common enough in Rome even before Augustus came to power, it was this first emperor of Rome# who made a political art form of collecting the children of his enemies. Selene grew up amongst a houseful of children in what the French historian Auguste Bouche-Leclercq would call “the lamentable embassy of royal orphans.”

Some of these orphans were her own brothers and sisters, her father’s children by other wives. Iullus Antonius, the only one of Antony’s Roman sons to survive, probably last saw his father when he was seven years old and was formally brought into Augustus’ household when he was eleven. His mother died while he was still a toddler, so he likely had few memories of her. Augustus’ family may have been the only family that Iullus ever knew and he was granted extraordinary favors by the emperor–who gave his own niece Marcella to Iullus in marriage. (Still, a full-blooded heir of Antony was a dangerous man to leave alive, and this may have been Iullus’ undoing later in life.)

Another of the children Augustus collected for his political stratagems was Juba, son of a fierce Numidian king of the same name who chose the wrong side in a war against Rome and paid the price for it with his life. Juba was quite possibly an infant when his father was forced to suicide and no older than five years old when he was displayed in Caesar’s triumph. Unlike Selene, he would have no memories of his homeland nor siblings with whom to recount the tragedies of his young life. He was raised as a Roman boy and the family of Augustus was the only family he knew. Juba was a prodigy, recognized for his scholarship before the age of twenty. He served Augustus in a military capacity in Spain, and possibly before then in the war against Selene’s parents, and went on to become Selene’s husband and Rome’s most trusted client king.

Selene came to Rome in chains but left as a Queen and both she and her husband proved to be such fine examples of what could be accomplished by this policy of benign hostage-taking, that it would become a central hallmark of the Augustan Regime. Augustus would transform a boy named Hyginos who had been taken from Spain into his chief librarian. He would host the sons of King Herod so as to determine which of them might make a better heir for the troubled Judean kingdom. He would return a hostage prince to the Parthians in exchange for a peace treaty only to later host Parthian princes as guests, to indoctrinate them in the Roman way.

From our modern vantage point, there’s something decidedly sinister about using children in this way, and my novel examines the personal toll it might take on a little girl. But I must also point out that the policy was wildly successful and helped cement nearly a hundred years of relative peace that would come to be known as the Pax Romana.