The differences between Castile, Aleppo, and Marseille soaps are mainly four. First of all their geographic origins. Aleppo is in the Middle East while the other two are in Europe. Second, the period of time when their recipes were first elaborated. Even though historians are not sure of the exact date Middle Eastern soap was first produced, they all agree that it was first elaborated first in Aleppo, Syria. Production in that city started at least 2000 years ago, in Europe soap was introduced in the early 16th century. The third difference between those soaps is the manufacturing technique. Castile soap is saponified at cold temperatures while the other two are boiled for an extended period of time. Depending on the richness of the soil and the seasons some olives won’t saponify at cold temperatures thus requiring boiling. Finally, the last difference between those soaps is the concentration of oils used in the mix. Aleppo soap is known to have laurel oil among its ingredients at varying concentrations while the other two are mainly 100% olive oil. Ancient recipes have changed with time, but the main ingredient remains olive oil which is abundant in the Mediterranean area.