No mystery about it — a rare copy of Edgar Allan Poe’s first book sold at auction yesterday for a record $662,500.

“Tamerlane and Other Poems,” published anonymously in 1827 — when Poe was 18 — went under the hammer at Christie’s and set a record for 19th- century poetry books.

One of 12 copies in existence, the book went to an unidentified collector in the United States.

“It is the first work of a major American author and international popular-culture superstar, said Poe scholar Paul Lewis.