Argead dynasty
His mother Theoxena was a Greek Macedonian noblewoman. She was the second daughter and third child born to the noblewoman Berenice I and her first husband obscure nobleman Philip. Archagathus’ biological maternal grandfather Philip, served as a military officer in the service of the Greek King Alexander the Great and was known in commanding one division of the Phalanx in Alexander’s wars. Archagathus’ maternal grandmother Berenice I, was the great-niece of the powerful Regent Antipater and she was a distant collateral relative to the Argead dynasty. His full blooded maternal uncle was Magas of Cyrene and his full-blooded maternal aunt was Antigone.