Scipio Nasica, are also historical personages.

I chose the latter from among the many young patricians living at the
time, partly on account of the strong aristocratic feeling which he
displayed, particularly in his later life, and partly because his
nickname of Serapion struck me. This name I account for in my own way,
although I am aware that he owed it to his resemblance to a person of
inferior rank.

For the further enlightenment of the reader who is not familiar with this
period of Egyptian history I may suggest that Cleopatra, the wife of
Ptolemy Philometor--whom I propose to introduce to the reader--must not
be confounded with her famous namesake, the beloved of Julius Caesar and
Mark Antony. The name Cleopatra was a very favorite one among the
Lagides, and of the queens who bore it she who has become famous through
Shakespeare (and more lately through Makart) was the seventh, the sister
and wife of Ptolemy XIV. Her tragical death from the bite of a viper or
asp did not occur until 134 years later than the date of my narrative,
which I have placed 164 years B.C.

At that time Egypt had already been for 169 years subject to the rule of
a Greek (Macedonian) dynasty, which owed its name as that of the
Ptolemies or Lagides to its founder Ptolemy Soter, the son of Lagus.
This energetic man, a general under Alexander the Great, when his
sovereign--333 B.C.--had conquered the whole Nile Valley, was appointed
governor of the new Satrapy; after Alexander's death in 323 B.C., Ptolemy
mounted the throne of the Pharaohs, and he and his descendants ruled over
Egypt until after the death of the last and most famous of the
Cleopatras, when it was annexed as a province to the Roman Empire.