Arsinoe, I

http://en.wikipedia.org/wiki/Arsinoe_of_Macedonia

Arsinoe of Macedonia (Greek: Ἀρσινόη; lived 4th century BC) was the mother of Ptolemy I Soter (323 BC – 283 BC), king of Egypt. She was originally a concubine of Philip II, king of Macedon, and it is said she was given by Philip to Lagus, a Macedonian, while she was pregnant with Ptolemy. Ptolemy was regarded by the Macedonians as the son of Philip.

NB: this is revisionist history that was created after the death of Alexander.

Ptolemy was the son of the nobleman Lagus, a native of the Macedonian district of Eordaea whose family was undistinguished until Ptolemy’s time, and of Arsinoe, who was related to the Macedonian Argead dynasty. He was probably educated as a page at the royal court of Macedonia, where he became closely associated with Alexander.

http://en.wikipedia.org/wiki/Arsinoe_of_Macedonia