Mordechai is a significant figure in the biblical Book of Esther. He is known for his role as a Jewish leader in the Persian Empire and is the cousin and guardian of Esther, the queen. Mordechai is celebrated for his bravery and wisdom, particularly in standing up against Haman, an advisor to the king who plotted to destroy the Jewish people. Mordechai's actions ultimately led to the salvation of the Jews, and he is remembered during the festival of Purim. This holiday commemorates the events of the Book of Esther, highlighting themes of courage, identity, and the triumph of good over evil.