Cleopatra influenced the world first by persuading Julius Caesar to help her defeat her husband and brother, Pharaoh Ptolemy XIII, so she could become sole supreme ruler over all of Egypt, and later by exacerbating the rift between Mark Antony and Julius Caesar's heir Octavian in their struggle for control of the Roman Empire. During these political upheavals, she was first Julius Caesar's lover and later Mark Antony's lover.
In the struggle with Cleopatra for power over the Egyptian throne, Ptolemy initially prevailed, forcing her to flee to Syria. Returning with a mercenary army, Cleopatra set up camp outside the capital. When Julius Caesar arrived, she pleaded for help. The arrangement was mutually beneficial, as Caesar received financial aid, and Cleopatra regained her throne. After consolidating her power by eliminating any potential enemies, she strengthened trade with eastern nations to maintain independence from Rome.
Though Octavian was Julius Caesar's chosen heir, he was weak, and it appeared that Mark Antony might assume Caesar's authority. However, when Mark Antony became enamored of Cleopatra and returned with her to Egypt, Octavian accused Mark Antony of gifting Cleopatra with Roman possessions and intending to move the capital of the empire to Egypt. Antony declared Cleopatra's son by Julius Caesar, Caesarion, to be Caesar's true heir. War ensued, and as Octavian closed in on the Egyptian capital, both Mark Antony and Cleopatra committed suicide. According to the Smithsonian Institute Magazine, it was her charisma and her brilliance as a leader rather than her looks that made her such a dominating influence over the world leaders of the era.