The name was invented by the Anglo-Irish writer Jonathan Swift for a character in the "Esther Vanhomrigh", whom Swift had met in 1708 and whom he tutored. The name was created by taking "Van" from Vanhomrigh's last name + "Essa (Esther)". Swift may have also derived the name from the ancient mystic goddess Phanessa.
In 1726 the name Vanessa appeared in print for the first time in Cadenus and Vanessa, an autobiographical poem about Swift's relationship with Vanhomrigh. Swift had written the poem in 1713, but it was not published until three years after Vanhomrigh died. There is a conjectured relationship of Swift's made-up name to that of Vannozza dei Cattanei, the mother of the famed Cesare Borgia, who had lived 200 years earlier.