Bérénice IV, half-sister of Cleopatra VII, reigned over Egypt from 58 to 55 BC. She is the daughter of Ptolemy XII, of the Lagide dynasty, king of Egypt.
In -58, after the annexation of Cyprus by the Roman Republic, the Egyptian people overthrew Ptolemy XII who fled in Rome to seek help. His wife dies shortly after his departure and the people proclaim Berenice queen.
As a single woman ruling Egypt, she is expected to marry, but she does not. Her consuls then forced her to marry Seleucus VII, but she had him assassinated and remained alone to reign. Later, she marries Archelaus, but he does not become co-regent and she retains power alone.
After gaining the support of the Romans to return to power, Ptolemy XII corrupts the governor of Syria, Aulus Gabinius. He invaded Egypt with his troops in -55. and restores Ptolemy XII to the throne. Barely returned to power, he embarked on a series of executions and had Bérénice IV killed.