In the Mediterranean Basin, the Arabs were the first to develop soap with a sea salt base that was later used in North Africa, Spain, and in Provence. In the ninth century, Marseille became the center of soap manufacturing. During the Renaissance, Italian perfumers brought their expertise and "luxury soaps" (scented savonettes) were introduced. In the middle of the 20th century, the soap makers of the North of France developed a soap industry based on animal fats whereas soap makers in Marseille refused to abandon their use of vegetable oils. Competition was harsh and unbalanced as the cost of animal fats was substantially lower to that of vegetable oils. As a result, the soap industry in Marseille declined but remained true to its principles.
The first recipe for Marseille soap can be found in the 1751 Encyclopédie by Diderot and d'Alembert. By French law, any soap called "Marseille" must be made with a minimum of 72% vegetable oil and have no fragrance or color added to it. Soap is made by mixing oil, water and soda and boiling them in huge caldrons for 6 or 7 days. At that time, the soap acquires a violet scent. When olive oil is used, the paste shows a green coloration; when other vegetable oils are used, the paste is yellow-beige. The mixture is then placed in low basins and left to dry for about two weeks when it is to ready to be cut and stamped, either by hand or by machine. There is no additional processing or milling to make the soap hard and smooth; each batch of soap is a little bit different. Newly made soap is wet with moisture and very soft. When the soap is cut by hand, as in the case of our cubes of Marseille Soap, the soap requires a full month to dry. The dryer the soap is, the longer it lasts! Sometimes, the soft soaps will twist and lose their shape as they dry. The olive oil soaps will also change color, fading from dark green to light green, even tan and ocher: it is the result of the natural oxidation of the olive oil in the soap .
In some Marseille-style soaps, essential oils are added to the Marseille base to give fragrance and therapeutic properties to the soap (essential oils are the concentrated aromatic oils of plant leaves, flowers, seeds, barks, roots and the rind of some fruits).
Marseille and Marseille-style soaps are all natural, vegetable based and biodegradable; they are free of alcohol and synthetics. Non-drying and very moisturizing, they make a perfect choice for sensitive skins. These gentle soaps are still used in French households. In rural areas, it often is the only soap to be found in the house and is used in the kitchen, bath and laundry.