I'm presenting about henna at a local SCA event and I realized as I was putting my information together that it might be helpful for other artists and enthusiasts, so here you go! This is basically a compilation of previous research that I've done with links to further resources. Feel free to comment or email me with any additional sources or questions — I'd love to hear from you.
There aren't a lot of sources on the early (pre-medieval) history of henna, and I've outlined most of them on my website, here and here.
|Venus with red (hennaed) hair, 1st-2nd century CE|
Henna continued to be known and used in the Greco-Roman world, and traveled into Roman North Africa and even into mainland Europe. We have no direct evidence of henna's use as body art in the ancient world but it seems likely that they used it to dye skin as well as hair.
By the rise of Islam, henna was known as a medium for body art and was seen as feminine adornment in particular, although men used it as well to dye hair and beards. Early Islamic sources indicate that it was used by Jews and pagans in the Arabian peninsula, and that it was associated with joy and celebrations. It was favoured by the Prophet and his family and using henna became part of the sunnah [encouraged behaviour] and a mark of piety. There's more about henna in early Islam here and here.
There are two main areas where henna would have been an important part of cultural aesthetics during the 'SCA Period' — the Iberian peninsula (al-Andalus) / North Africa, and Persia. I'll offer some sources below for each of them, and then some reflections on what kinds of henna would not be "period."