Justa Grata Honoria
Justa Grata Honoria was the sister of the western Roman emperor Valentinian III.
She is most famous for writing a perhaps foolish letter to Attila the Hun in spring 450 asking him to save her from an unwanted marriage to a senator. Taking the letter - which came with her ring as proof it was sent by her - as a betrothal and thus an invitation to invade the Western Empire, Using the letter as has excuse and "asking for half of the western Empire as dowry", Attilla ravaged Gaul and Italy from 451 to 453.
When Valentinian discovered the plan, only the influence of their mother Galla Placidia convinced him to exile, rather than kill, Honoria.