Argead dynasty
Arsinoe was originally a concubine of Philip II, king of Macedon, and it is said she was given by Philip to Lagus, a Macedonian nobleman, while she was pregnant with Ptolemy I Soter I, but it is possible that this is a later myth fabricated to glorify the Ptolemaic Dynasty. Ptolemy was regarded by the Macedonians as the son of Philip. Alternately, Ptolemy's lineage to the Argead dynasty was shifted to Arsinoe in an attempt to legitimize his claim; in this case Arsinoe is daughter of Meleager, son of Balacrus, son of Amyntas, son of Alexander I of Macedon. However, contemporary and modern research indicates this to be a fabrication.