Question: Which event in Edgar Allan Poe's life has remained mysterious, prior to which became engaged to Sarah Elmira Royster Shelton, and was soon found delirious in Baltimore and in need of assistance?
Sentence (from "Death of Edgar Allan Poe"): The death of Edgar Allan Poe on October 7, 1849, has remained mysterious: the circumstances leading up to it are uncertain and the cause of death is disputed.
Relevant evidence: Yes