Final answer:
Creon, besides being Antigone's uncle, was also the brother-in-law of Oedipus and married to Jocasta, making him Antigone's great-uncle and a central figure in the royal family of Thebes.
Step-by-step explanation:
Besides being Antigone's uncle, Creon was also related to other members of the royal family of Thebes. He was the brother-in-law of Oedipus, having married Oedipus's sister Jocasta. This makes Creon both Antigone's great-uncle and her uncle by marriage, as Antigone was the daughter of Oedipus and his mother Jocasta—a result of the tragic incestuous marriage. After the deaths of Oedipus and his sons, Creon becomes the ruler of Thebes. This places Creon in a position of significant power, which he wields firmly as he deals with the aftermath of Oedipus's curse on their family and the fallout from the deaths of Eteocles and Polyneices, both brothers of Antigone.