Margot is the French short form of Marguerite — itself from the Greek margaron, meaning "pearl." Marguerite de Valois, queen of France in the 16th century, was known as "la Reine Margot" — Queen Margot.
Margot has been used in France for centuries. It entered the U.S. top 500 in 2014 and has been climbing ever since.
Margot 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 Margot reduce to 2, The Peacemaker. This is a traditional interpretive system, not a factual claim about the name.