henna on their nails and hair. Henna was also used to dye

As far back as  B.C. the ancient Egyptians were using henna on their nails and hair. Henna was also used to dye animal skins, textiles, and men's beards. It was many hundreds of years ago when the application of henna to a woman’s hands and feet first assumed the form of an intricate ritual. Henna is a good omen to be used during auspicious occasions such as weddings and religious festivals, births and naming ceremonies, circumcisions, birthdays and holidays.
Once the henna plant's cooling properties were discovered, painting the skin became a way for the desert people of India to cool down their body temperatures. Until the art of mehndi became hot news in 1996, henna was mostly used in the United States as a hair dye. Widely recognized now as a wonderful way to dye the skin and to achieve the look of a tattoo, traditional henna uses and application processes have gone contemporary.