That question already stirred the ancient historians.
Sophonisba or Sophoniba is believed to have been the daughter of Hasdrubal, son of Gesco, a Carthaginian general. She was married for political reasons to Syphax, a Numidian king of the Masaeisylians, as opposed the Gaia or Gala, king of the Massylians. Confusing, eh? Anyway, Gaia's son Massinissa, who was educated – kept as hostage? – in Carthage, was or believed himself betrothed to Sophonisba before she was given to Syphax. After the death of his father he returned to Africa from Spain where he had fought the Romans, and first was deprived of his kingdom by his brother – or uncle? – Oezalces, then by Syphax. While Syphax stayed in the Carthaginian camp, Massinissa went over to the Romans and Scipio. Hasdrubal and Syphax were defeated in the famous burned camp incident (Livy), and Massinissa pursued Syphax to Cirta, his capital, and took Syphax and Sophinisba as prisoners. He married the queen against Scipios wishes, and when Scipio insisted she must be taken to Rome for the triumph, Massinissa poisoned her and then gave her a royal funeral. Syphax survived and was taken to the triumph.
So was is politics, a love story, or both? Was Syphax the monster he sometimes is portrayed as?
According to Appian, Syphax bad-mouthed Sophonisba, she was reunited with Massinissa but went to her death willingly, Scipio called her a worthless woman, and Syphax died of grief in Rome. Massinissa became king of all Numidia.
Livy, in Book 30, concocts a flowering speech with which she bewitches Massinissa, and "…as the Numidians are an excessively amorous race, he became the slave of his captive".
Dio Cassius in a fragment and an epitome by Zonares confuses the issue even more but is more on the side of love and jealousy.
According to Wikipedia, "the story became the subject of
tragedies (and later operas) from the 16th to the 18th centuries. The first
tragedy is credited to the Italian Gian Giorgio Trissino (1524). In France,
Trissino's version was adapted by Mellin de Saint-Gelais (performed in 1556),
and may have served as the primary model for versions by Antoine de Montchrestien
(1596) and Nicolas de Montreux (1601). The tragedy by Jean Mairet (1634) is one
of the first monuments of French "classicism", and was followed by a
version from Pierre Corneille (1663). The story of Sophonisbe also served as
subject for works by John Marston (1606),
Nathaniel Lee (1676), James Thomson (1730), Voltaire, Vittorio Alfieri (1789), Daniel Lohenstein, Emmanuel Geibel, Henry
Purcell, Christopher Gluck, and others."
David Anthony Durham, in Pride of Carthage, portrays Sophonisba as the sister of Hannibal – which certainly avoids the
potentially confusing issue of introducing another Hasdrubal – and gives us a
tragic love story, with Syphax a villain through and through, and the Carthaginian
government a willing accomplice.
The above Coin of Massinissa, from livius.org, shows an unidentified man and a horse. The painting is by Giambattista Pittoni; click on image at the bottom of that page to get enlargement.There is also an engraving "Sophonisbe empties the poison cup" (Wikimedia Commons) by Georg Pencz.