Final answer:
The face that launched a thousand ships' is a reference to Helen of Troy. This phrase was used to highlight her beauty which indirectly led to the Trojan War. The war started when Helen eloped with Paris, the prince of Troy.
Step-by-step explanation:
The phrase 'the face that launched a thousand ships' refers to Helen of Troy, wife of King Menelaus of Sparta, during the Trojan War. This phrase comes from a line in the poem 'Doctor Faustus' by Christopher Marlowe, to underscore her beauty which was credited to have indirectly caused the Trojan War. When Helen eloped with Paris, the prince of Troy, her husband King Menelaus and his brother, King Agamemnon launched a massive military expedition, triggering the Trojan War, as depicted in Homer's epic, the Iliad.
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