As a mystical follower of the god Dionysus, Olympias was said to sleep with a giant snake in her bed as a pet and spiritual familiar. Apparently she convinced the young Alexander that in conceiving him she had been impregnated not by Philip but by Zeus, king of the gods. This devine parentage would have put Alexander on a par with the noblest heroes of myth.

Olympia gained much influence during Alexander's reign, and after his death plotted to secure power for her grandson by killing Alexander's half brother and successor. The Macedonian general Cassander besieged her at Pydna, and executed her on its surrender.