Originating in India, where it was considered a sacred herb, basil has spread West across the world. When the Greeks got ahold of it they dubbed it "basileus," which means "king." To Italians it is a sign of love, and Haitian legend says it came from the love goddess Erzulie.
Historically, women who worried that their husbands might be straying powdered their breasts with powdered basil. It's also an occasional ingredient in old love potions
The rich, minty fragrance of fresh basil is certainly enchanting, though conventional medicine (to my knowledge) has found nothing particularly aphrodisiac about the plant. Practitioners of alternative medicine sometimes use its essential oil to treat the Madonna/whore complex, but that seems to be the extent of it.