Olympias (Ὀλυμπιάς, c. 375-316 BCE) was the Epirote princess and mother of Alexander the Great — fourth wife of Philip II of Macedon. Famously fierce, she claimed descent from Achilles and was rumored to consort with snakes during religious rites.
Olympias does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
In Pythagorean numerology the letters of Olympias reduce to 2, The Peacemaker. This is a traditional interpretive system, not a factual claim about the name.