Darius did, however, ask who the Athenians were, and after receiving the answer, he called for his bow. This he took and, placing an arrow on it, shot it into the sky, praying as he sent it aloft, “O, Zeus, grant me vengeance on the Athenians.” Then he ordered one of his servants to say to him three times whenever dinner was set before him, “Master, remember the Athenians.”

What does this description of Darius I reveal about him?