* Ancient Times: Evidence suggests that people have been coloring their nails for thousands of years. In ancient China, around 3000 BC, both men and women used a mixture of beeswax, gum arabic, and egg whites to create nail polish. The Egyptians also used henna and other natural dyes to paint their nails.
* Medieval Period: In Europe during the Middle Ages, nail polish was primarily used by the wealthy and aristocracy. It was often associated with royalty and nobility.
* Modern Times: The development of synthetic nail polish really took off in the 20th century. In 1920, Revlon introduced the first commercially available nail polish in the United States. This launched a new era of nail polish, with countless colors, textures, and finishes becoming available.
So, to answer your question more directly:
* Early forms of nail polish were used in ancient times, possibly as early as 3000 BC.
* Modern, commercially available nail polish first appeared in the 1920s.
It's worth noting that there's still ongoing research and debate about the earliest uses of nail polish. New discoveries and interpretations of ancient artifacts continue to shed light on this history.