Why did Mark Antony form an alliance with Cleopatra of Egypt?

The alliance between Mark Antony and Cleopatra was driven by a combination of personal affection and significant political and military necessity.12

While the two shared a long-term partnership and had three children together, their cooperation served distinct strategic goals for both parties:

• Antony’s Needs: As he prepared for a major military campaign against Parthia, Antony required the vast resources of Egypt. The kingdom served as a vital source of both funding and military supplies for his forces.12
• Cleopatra’s Needs: Cleopatra sought to restore the former glory and territorial reach of the Ptolemaic kingdom. She relied on Antony’s influence and military power to help her reclaim lost dominions.12

Their partnership was eventually exploited by Octavian, who used the alliance as a propaganda tool in Rome. He depicted their relationship as a threat to Roman interests, claiming that Antony intended to transfer Roman territories to Greek control, which ultimately led to the declaration of war against Cleopatra and the eventual downfall of both leaders.1