Berenice IV of Egypt
Berenice was the daughter of Ptolemy XII Auletes and probably Cleopatra V Tryphaena. She was the sister of the famous Pharaoh Cleopatra, Arsinoe IV, Ptolemy XIII Theos Philopator and Ptolemy XIV. In 58 BC, Ptolemy XII and Cleopatra VII fled to Rome in search of political and military aid against Berenice's elder sister Cleopatra VI Tryphaena, who had become far too powerful.
After Tryphaena's death in 57 BC, possibly poisoned on behalf of Berenice, she at age 20 became the sole ruler of Egypt due to her father's absence, and with him and Cleopatra absent she had no worry about being overthrown or overpowered and executed.
As a lone woman ruling Egypt, she was expected to marry and have a man as a co-regent. When she did not, her consuls forced her to marry prince Seleucus VII Philometor, but she had him strangled and remained as sole ruler. The public feared the Ptolemaic reign would fail to continue due to Berenice's refusal to marry. It is also believed she cared far too much for fashion and luxuries, leading to rising expenses. She later married Archelaus, but he was not co-regent. Archelaus had been appointed to the priesthood at Comana at Cappadocia by Pompey, and claimed to be a son of King Mithridates VI of Pontus. Strabo instead says his father was Archelaus, a general of Mithridates VI in the First Mithridatic War who defected to the Romans.
The reign of Berenice ended in 55 BC when her father retook the throne with the aid of the Romans led by Aulus Gabinius, and had Berenice beheaded. Archelaus, who according to Strabo had previously had a friendly relationship with Gabinius, died in battle against the forces of Gabinius.