At the height of the Ottoman Empire, olive oil soap from the Holy Land was a staple throughout the Middle East, and a luxury in Medieval Europe. 

Its chief ingredients are virgin olive oil (the main agricultural product of the region), water, and an alkaline sodium compound. The finished product is ivory-coloured and has almost no scent. Some modern varieties have scent added. 

Castile soap is a name used in Europe for olive oil based soap made in a style similar to that originating in the Castile region of Spain. The origins of Castile soap go back to the Levant, where soap-makers have made hard soaps based on olive and laurel oil for millennia.