But back in the day, aka in ancient Greece, flower crowns were literally a godly symbol: The Greeks depicted their gods and goddesses wearing wreaths of certain plants dedicated to them. Romans took it to the next level by wearing flower wreaths at Floralia, a Roman celebration of the goddess Flora, which was pretty nuts even by modern standards: Prostitutes would perform naked, and deer and rabbits were released into stadiums.
So flower crowns were associated with sexy pagan festivals, which the Christians didn’t like so much. Upon the rise of Christianity, flower crowns faded from use until they were later revived during the Renaissance, when Europeans took renewed interest in Greek and Roman literature. They spread throughout Europe and eventually to the United States, finding different uses in different cultures — including the hippie “flower power” movement of the ’70s, which is what we often associate them with today.