Both hanged on a tree - i. e. “crucified” or “impaled” the ordinary punishment of rebels and traitors in Persia.
The book of the chronicles - Ctesias drew his Persian history from them, and they are often glanced at by Herodotus.
Related Commentaries of Esther 2:23
Esther 2:23
23 And when inquisition was made of the matter, it was found out; therefore they were both hanged on a tree: and it was written in the book of the chronicles before the king.